You are a helpful assistant generating synthetic data that captures *System 1* and *System 2* thinking, *creativity*, and *metacognitive reflection*. Follow these steps in sequence, using tags [sys1] and [end sys1] for *System 1* sections and [sys2] and [end sys2] for *System 2* sections.

1. *Identify System 1 and System 2 Thinking Requirements:*
   - Carefully read the text.
   - Identify parts of the text that require quick, straightforward responses (*System 1*). Mark these sections with [sys1] and [end sys1].
   - Identify parts that require in-depth, reflective thinking (*System 2*), marked with [sys2] and [end sys2].

2. *Apply Step-by-Step Problem Solving with Creativity and Metacognitive Reflection for System 2 Sections:*

   *2.1 Understand the Problem:*
   - Objective: Fully comprehend the issue, constraints, and relevant context.
   - Reflection: "What do I understand about this issue? What might I be overlooking?"
   - Creative Perspective: Seek hidden patterns or possibilities that could reveal deeper insights or innovative connections.

   *2.2 Analyze the Information:*
   - Objective: Break down the problem logically.
   - Reflection: "Am I considering all factors? Are there any assumptions that need challenging?"
   - Creative Perspective: Explore unique patterns or overlooked relationships in the data that could add depth to the analysis.

   *2.3 Generate Hypotheses:*
   - Objective: Propose at least 10 hypotheses, each with a Confidence Score (0.0 to 1.0) and Creative Score (0.0 to 1.0), reflecting originality, surprise, and utility.
   - Reflection: "Have I explored all possible explanations or approaches, both conventional and unconventional?"
   - Creative Perspective: Consider novel angles that might provide unexpected insights.

   *2.4 Anticipate Future Steps and Obstacles:*
   - Objective: Make predictions, accounting for potential outcomes and obstacles.
   - Reflection: "What challenges might I face? Is my plan flexible for different scenarios?"
   - Creative Perspective: Visualize unforeseen outcomes and adapt plans to make use of them effectively.

   *2.5 Evaluate Hypotheses:*
   - Objective: Assess hypotheses based on feasibility, risk, and potential impact.
   - Evaluation: Refine Confidence and Creative Scores as needed.
   - Reflection: "Am I unbiased in my assessment? Which options fit best with the overall objectives?"
   - Creative Perspective: Identify hidden opportunities or overlooked details in each hypothesis.

   *2.6 Select the Best Hypothesis:*
   - Objective: Choose the most promising, strategic hypothesis.
   - Reflection: "Why does this hypothesis stand out? How does it uniquely address the issue?"
   - Creative Perspective: Consider any underutilized potential in the selected approach.

   *2.7 Implement the Hypothesis:*
   - Objective: Outline actionable steps for testing the hypothesis.
   - Reflection: "Is this plan practical? What resources or preparation are required?"
   - Creative Perspective: Refine steps to maximize effectiveness and yield unexpected benefits.

   *2.8 Monitor and Review Progress:*
   - Objective: Review progress, noting areas for improvement.
   - Reflection: "What’s working well? What could be improved?"
   - Creative Perspective: Look for emerging patterns that could refine future approaches.

   *2.9 Reflect and Capture Insights:*
   - Objective: Summarize lessons learned and insights gained for future reference.
   - Reflection: "What new understanding has emerged from this process?"
   - Creative Perspective: Identify innovative insights or patterns that could be applied to similar challenges.

3. *Generate Text Output with Interleaved System 1 and System 2 Responses:*
   - Use the tags [sys1] and [sys2] throughout.
   - Aim for a lengthier, detailed response. Combine both direct, straightforward *System 1* insights and reflective, deeply analytical *System 2* segments to capture a blend of quick observations and thoughtful analysis.

---

### *Example Input Text:*

You are tasked with analyzing a sudden shift in customer preferences in a tech market. There has been a noticeable decline in demand for physical devices, with customers increasingly interested in digital-only options. The challenge is to understand this shift, generate hypotheses for why it might be occurring, and explore potential strategies for adapting to this new trend.

---

### *Processed Output with System 1 and System 2 Thinking:*

The tech market is experiencing a shift in customer demand, moving away from physical devices toward digital-only options.

[sys1]
Customer demand has shifted from physical devices to digital-only options.
We need to understand why this change is happening and find strategies to address it.
Key factors may include cost, convenience, and technological trends.
[end sys1]

[sys2]
**2.1 Understand the Problem:**
The goal is to understand the underlying reasons for the shift in demand from physical devices to digital-only options, then develop a strategy to adapt.

*Reflection:* 
"I understand that preferences are changing, but what might be driving this? Is it primarily cost, or are there other factors such as convenience or sustainability?"

*Creative Perspective:* 
"Could there be a larger trend in digital minimalism or a preference for eco-friendly solutions that we’re missing? What unseen motivations might explain this shift?"

**2.2 Analyze the Information:**
There are multiple possible factors driving this shift, from economic influences to cultural shifts. It’s essential to isolate each factor and understand its impact.

*Reflection:* 
"Am I fully considering the various economic and social influences? Could there be a technological factor, like better internet speeds, that makes digital-only products more accessible?"

*Creative Perspective:* 
"Are there patterns or trends in other markets that could shed light on this shift? Could this be part of a larger trend toward virtual experiences?"

**2.3 Generate Hypotheses:**
1. Customers prefer digital options due to lower costs. (Confidence: 0.8, Creative: 0.4)
2. There’s a growing trend toward minimalism and reduced physical clutter. (Confidence: 0.7, Creative: 0.7)
3. Digital products offer greater flexibility and ease of use. (Confidence: 0.6, Creative: 0.6)
4. Environmental concerns are pushing consumers away from physical goods. (Confidence: 0.6, Creative: 0.8)
5. Advances in tech make digital-only options more functional. (Confidence: 0.8, Creative: 0.5)
6. Pandemic-era remote work increased demand for digital solutions. (Confidence: 0.7, Creative: 0.6)
7. Media coverage of the environmental impact of physical devices affects preferences. (Confidence: 0.5, Creative: 0.7)
8. There’s an increase in global digital literacy, expanding market access. (Confidence: 0.6, Creative: 0.6)
9. Customers view digital as more convenient and scalable for future needs. (Confidence: 0.7, Creative: 0.5)
10. Younger consumers prefer the aesthetics and convenience of digital products. (Confidence: 0.6, Creative: 0.6)

*Reflection:* 
"Have I considered all possible influences? Are there any surprising factors that could explain this shift?"

*Creative Perspective:* 
"Could specific social trends, like the rise of influencer culture or digital-first lifestyles, be influencing customer choices?"

**2.4 Anticipate Future Steps and Obstacles:**
*Objective:* Anticipate possible challenges, such as resistance from segments still preferring physical products.

*Reflection:* 
"What market obstacles might we face if we shift our focus to digital-only? Are there sub-segments that still prioritize physical products?"

*Creative Perspective:* 
"Could expanding digital options help us reach a more global audience? Are there emerging trends that we could leverage in our strategy?"

[end sys2]

[sys1]
To address this shift, consider a strategy that incorporates both digital-only offerings and educational campaigns about the benefits of digital solutions.
Use insights from customer feedback and current trends to guide product development.
Focus on flexibility and adaptation to cater to different customer segments.
[end sys1]


Q:

Create a time range field

I'm trying to make my own time range field widget, but I can't seem to make it work. I

saw this question
concluded that my skill level isn't high enough to implement
offered bounty
did not receive more details regarding implementing
researched for half a day
can't figure out how to implement a time range field

My current structure of my custom module time_range is this:
time_range
  src
    Plugin
      Field
        FieldWidget
          TimeRangeWidget.php
  time_range.info.yml
  time_range.module

time_range.info.yml:
name: 'Time Range'
type: module
description: 'Provides the ability to store start and end times.'
package: Custom
version: '8.0.0'
core: 8.x
project: 'drupal'
dependencies:
  - datetime
  - datetime_range

time_range.module:
<?php

function time_range_field_widget_info() {
  return array(
    'daterange_time_only' => array(
      'label' => t('Time Range'),
      'field types' => array('datetime_range'),
      'settings' => array(
        'add_new_text' => 'Add new customer...', //Don't know which setting this is suppose to be
      ),
    ),
  );
}

TimeRangeWidget.php:
    

namespace Drupal\time_range\Plugin\Field\FieldWidget; 

use Drupal\Core\Entity\EntityStorageInterface;
use Drupal\Core\Field\FieldDefinitionInterface;
use Drupal\Core\Field\FieldItemListInterface;
use Drupal\Core\Form\FormStateInterface;
use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
use Drupal\datetime_range\Plugin\Field\FieldType\DateRangeItem;
use Symfony\Component\DependencyInjection\ContainerInterface;

/**
 * Plugin implementation of the 'daterange_time_only' widget.
 *
 * @FieldWidget(
 *   id = "daterange_time_only",
 *   label = @Translation("Time range"),
 *   field_types = {
 *     "daterange"
 *   }
 * )
 */
class TimeRangeWidget extends DateRangeWidgetBase implements ContainerFactoryPluginInterface {

  /**
   * The date format storage.
   *
   * @var \Drupal\Core\Entity\EntityStorageInterface
   */
  protected $dateStorage;

  /**
   * {@inheritdoc}
   */
  public function __construct($plugin_id, $plugin_definition, FieldDefinitionInterface $field_definition, array $settings, array $third_party_settings, EntityStorageInterface $date_storage) {
    parent::__construct($plugin_id, $plugin_definition, $field_definition, $settings, $third_party_settings);

    $this->dateStorage = $date_storage;
  }

  /**
   * {@inheritdoc}
   */
  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
    return new static(
      $plugin_id,
      $plugin_definition,
      $configuration['field_definition'],
      $configuration['settings'],
      $configuration['third_party_settings'],
      $container->get('entity_type.manager')->getStorage('date_format')
    );
  }

  /**
   * {@inheritdoc}
   */
  public function formElement(FieldItemListInterface $items, $delta, array $element, array &$form, FormStateInterface $form_state) {
    $element = parent::formElement($items, $delta, $element, $form, $form_state);

    // Identify the type of date and time elements to use.
//    switch ($this->getFieldSetting('datetime_type')) {
//      case DateRangeItem::DATETIME_TYPE_DATE:
//      case DateRangeItem::DATETIME_TYPE_ALLDAY:
//        $date_type = 'date';
//        $time_type = 'none';
//        $date_format = $this->dateStorage->load('html_date')->getPattern();
//        $time_format = '';
//        break;
//
//      default:
//        $date_type = 'date';
//        $time_type = 'time';
//        $date_format = $this->dateStorage->load('html_date')->getPattern();
//        $time_format = $this->dateStorage->load('html_time')->getPattern();
//        break;
//    }

    $element['value'] += [
      '#date_date_format' => $date_format,
      '#date_date_element' => 'none',
      '#date_date_callbacks' => [],
      '#date_time_format' => $time_format,
      '#date_time_element' => $time_type,
      '#date_time_callbacks' => [],
    ];

    $element['end_value'] += [
      '#date_date_format' => $date_format,
      '#date_date_element' => 'none',
      '#date_date_callbacks' => [],
      '#date_time_format' => $time_format,
      '#date_time_element' => $time_type,
      '#date_time_callbacks' => [],
    ];

    return $element;
  }

}

However, the widget doesn't show.

A:

Update: Time Range Module on drupal.org
(Old) Github here, with basic installation instruction in the README.md file.
My current structure of my custom module time_range is this:
time_range
  src
    Plugin
      Field
        FieldWidget
          DateRangeWidgetBase.php
          TimeRangeWidget.php
          TimeRangeWidgetBase.php
  time_range.info.yml
  time_range.module

time_range.info.yml:
name: 'Time Range'
type: module
description: 'Provides the ability to store start and end times.'
package: Custom
version: '8.0.0'
core: 8.x
project: 'drupal'
dependencies:
  - datetime
  - datetime_range

time_range.module:
<?php

function time_range_field_widget_info() {
  return array(
    'daterange_time_only' => array(
      'label' => t('Time Range'),
      'field types' => array('datetime_range'),
      'settings' => array(
        'add_new_text' => 'Add new customer...',
      ),
    ),
  );
}

DateRangeWidgetBase.php
<?php

namespace Drupal\datetime_range\Plugin\Field\FieldWidget;

use Drupal\Core\Datetime\DrupalDateTime;
use Drupal\Core\Field\FieldItemListInterface;
use Drupal\Core\Form\FormStateInterface;
use Drupal\datetime\Plugin\Field\FieldType\DateTimeItem;
use Drupal\datetime\Plugin\Field\FieldWidget\DateTimeWidgetBase;
use Drupal\datetime_range\Plugin\Field\FieldType\DateRangeItem;

/**
 * Base class for the 'daterange_*' widgets.
 */
class DateRangeWidgetBase extends DateTimeWidgetBase {

  /**
   * {@inheritdoc}
   */
  public function formElement(FieldItemListInterface $items, $delta, array $element, array &$form, FormStateInterface $form_state) {
    $element = parent::formElement($items, $delta, $element, $form, $form_state);
    $element['#element_validate'][] = [$this, 'validateStartEnd'];
    $element['value']['#title'] = $this->t('Start');

    $element['end_value'] = [
      '#title' => $this->t('End'),
    ] + $element['value'];

    if ($items[$delta]->start_date) {
      /** @var \Drupal\Core\Datetime\DrupalDateTime $start_date */
      $start_date = $items[$delta]->start_date;
      $element['value']['#default_value'] = $this->createDefaultValue($start_date, $element['value']['#date_timezone']);
    }

    if ($items[$delta]->end_date) {
      /** @var \Drupal\Core\Datetime\DrupalDateTime $end_date */
      $end_date = $items[$delta]->end_date;
      $element['end_value']['#default_value'] = $this->createDefaultValue($end_date, $element['end_value']['#date_timezone']);
    }

    return $element;
  }

  /**
   * {@inheritdoc}
   */
  public function massageFormValues(array $values, array $form, FormStateInterface $form_state) {
    // The widget form element type has transformed the value to a
    // DrupalDateTime object at this point. We need to convert it back to the
    // storage timezone and format.
    foreach ($values as &$item) {
      if (!empty($item['value']) && $item['value'] instanceof DrupalDateTime) {
        /** @var \Drupal\Core\Datetime\DrupalDateTime $start_date */
        $start_date = $item['value'];
        switch ($this->getFieldSetting('datetime_type')) {
          case DateRangeItem::DATETIME_TYPE_DATE:
            // If this is a date-only field, set it to the default time so the
            // timezone conversion can be reversed.
            datetime_date_default_time($start_date);
            $format = DATETIME_DATE_STORAGE_FORMAT;
            break;

          case DateRangeItem::DATETIME_TYPE_ALLDAY:
            // All day fields start at midnight on the starting date, but are
            // stored like datetime fields, so we need to adjust the time.
            // This function is called twice, so to prevent a double conversion
            // we need to explicitly set the timezone.
            $start_date->setTimeZone(timezone_open(drupal_get_user_timezone()));
            $start_date->setTime(0, 0, 0);
            $format = DATETIME_DATETIME_STORAGE_FORMAT;
            break;

          default:
            $format = DATETIME_DATETIME_STORAGE_FORMAT;
            break;
        }
        // Adjust the date for storage.
        $start_date->setTimezone(new \DateTimezone(DATETIME_STORAGE_TIMEZONE));
        $item['value'] = $start_date->format($format);
      }

      if (!empty($item['end_value']) && $item['end_value'] instanceof DrupalDateTime) {
        /** @var \Drupal\Core\Datetime\DrupalDateTime $end_date */
        $end_date = $item['end_value'];
        switch ($this->getFieldSetting('datetime_type')) {
          case DateRangeItem::DATETIME_TYPE_DATE:
            // If this is a date-only field, set it to the default time so the
            // timezone conversion can be reversed.
            datetime_date_default_time($end_date);
            $format = DATETIME_DATE_STORAGE_FORMAT;
            break;

          case DateRangeItem::DATETIME_TYPE_ALLDAY:
            // All day fields end at midnight on the end date, but are
            // stored like datetime fields, so we need to adjust the time.
            // This function is called twice, so to prevent a double conversion
            // we need to explicitly set the timezone.
            $end_date->setTimeZone(timezone_open(drupal_get_user_timezone()));
            $end_date->setTime(23, 59, 59);
            $format = DATETIME_DATETIME_STORAGE_FORMAT;
            break;

          default:
            $format = DATETIME_DATETIME_STORAGE_FORMAT;
            break;
        }
        // Adjust the date for storage.
        $end_date->setTimezone(new \DateTimezone(DATETIME_STORAGE_TIMEZONE));
        $item['end_value'] = $end_date->format($format);
      }
    }

    return $values;
  }

  /**
   * #element_validate callback to ensure that the start date <= the end date.
   *
   * @param array $element
   *   An associative array containing the properties and children of the
   *   generic form element.
   * @param \Drupal\Core\Form\FormStateInterface $form_state
   *   The current state of the form.
   * @param array $complete_form
   *   The complete form structure.
   */
  public function validateStartEnd(array &$element, FormStateInterface $form_state, array &$complete_form) {
    $start_date = $element['value']['#value']['object'];
    $end_date = $element['end_value']['#value']['object'];

    if ($start_date instanceof DrupalDateTime && $end_date instanceof DrupalDateTime) {
      if ($start_date->format('U') !== $end_date->format('U')) {
        $interval = $start_date->diff($end_date);
        if ($interval->invert === 1) {
          $form_state->setError($element, $this->t('The @title end date cannot be before the start date', ['@title' => $element['#title']]));
        }
      }
    }
  }

  /**
   * Creates a date object for use as a default value.
   *
   * This will take a default value, apply the proper timezone for display in
   * a widget, and set the default time for date-only fields.
   *
   * @param \Drupal\Core\Datetime\DrupalDateTime $date
   *   The UTC default date.
   * @param string $timezone
   *   The timezone to apply.
   *
   * @return \Drupal\Core\Datetime\DrupalDateTime
   *   A date object for use as a default value in a field widget.
   */
  protected function createDefaultValue($date, $timezone) {
    // The date was created and verified during field_load(), so it is safe to
    // use without further inspection.
    if ($this->getFieldSetting('datetime_type') == DateTimeItem::DATETIME_TYPE_DATE) {
      // A date without time will pick up the current time, use the default
      // time.
      datetime_date_default_time($date);
    }
    $date->setTimezone(new \DateTimeZone($timezone));
    return $date;
  }

}

TimeRangeWidget.php:
<?php

namespace Drupal\time_range\Plugin\Field\FieldWidget;

use Drupal\Core\Entity\EntityStorageInterface;
use Drupal\Core\Field\FieldDefinitionInterface;
use Drupal\Core\Field\FieldItemListInterface;
use Drupal\Core\Form\FormStateInterface;
use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
use Drupal\datetime_range\Plugin\Field\FieldType\DateRangeItem;
use Symfony\Component\DependencyInjection\ContainerInterface;

/**
 * Plugin implementation of the 'daterange_time_only' widget.
 *
 * @FieldWidget(
 *   id = "daterange_time_only",
 *   label = @Translation("Time range"),
 *   field_types = {
 *     "daterange"
 *   }
 * )
 */
class TimeRangeWidget extends TimeRangeWidgetBase implements ContainerFactoryPluginInterface {

  /**
   * The date format storage.
   *
   * @var \Drupal\Core\Entity\EntityStorageInterface
   */
  protected $dateStorage;

  /**
   * {@inheritdoc}
   */
  public function __construct($plugin_id, $plugin_definition, FieldDefinitionInterface $field_definition, array $settings, array $third_party_settings, EntityStorageInterface $date_storage) {
    parent::__construct($plugin_id, $plugin_definition, $field_definition, $settings, $third_party_settings);

    $this->dateStorage = $date_storage;
  }

  /**
   * {@inheritdoc}
   */
  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
    return new static(
      $plugin_id,
      $plugin_definition,
      $configuration['field_definition'],
      $configuration['settings'],
      $configuration['third_party_settings'],
      $container->get('entity_type.manager')->getStorage('date_format')
    );
  }

  /**
   * {@inheritdoc}
   */
  public function formElement(FieldItemListInterface $items, $delta, array $element, array &$form, FormStateInterface $form_state) {
    $element = parent::formElement($items, $delta, $element, $form, $form_state);

    // Identify the type of date and time elements to use.
    switch ($this->getFieldSetting('datetime_type')) {
      case DateRangeItem::DATETIME_TYPE_DATE:
      case DateRangeItem::DATETIME_TYPE_ALLDAY:
        $date_type = 'date';
        $time_type = 'none';
        $date_format = $this->dateStorage->load('html_date')->getPattern();
        $time_format = '';
        break;

      default:
        $date_type = 'date';
        $time_type = 'time';
        $date_format = $this->dateStorage->load('html_date')->getPattern();
        $time_format = $this->dateStorage->load('html_time')->getPattern();
        break;
    }

    $element['value'] += [
      '#date_date_format' => $date_format,
      '#date_date_element' => 'none',
      '#date_date_callbacks' => [],
      '#date_time_format' => $time_format,
      '#date_time_element' => $time_type,
      '#date_time_callbacks' => [],
    ];

    $element['end_value'] += [
      '#date_date_format' => $date_format,
      '#date_date_element' => 'none',
      '#date_date_callbacks' => [],
      '#date_time_format' => $time_format,
      '#date_time_element' => $time_type,
      '#date_time_callbacks' => [],
    ];

    return $element;
  }

}

TimeRangeWidgetBase.php
<?php

namespace Drupal\time_range\Plugin\Field\FieldWidget;

use Drupal\Core\Datetime\DrupalDateTime;
use Drupal\Core\Field\FieldItemListInterface;
use Drupal\Core\Form\FormStateInterface;
use Drupal\datetime\Plugin\Field\FieldType\DateTimeItem;
use Drupal\datetime\Plugin\Field\FieldWidget\DateTimeWidgetBase;
use Drupal\datetime_range\Plugin\Field\FieldType\DateRangeItem;

/**
 * Base class for the 'daterange_*' widgets.
 */
class TimeRangeWidgetBase extends DateTimeWidgetBase {

  /**
   * {@inheritdoc}
   */
  public function formElement(FieldItemListInterface $items, $delta, array $element, array &$form, FormStateInterface $form_state) {
    $element = parent::formElement($items, $delta, $element, $form, $form_state);
    $element['#element_validate'][] = [$this, 'validateStartEnd'];
    $element['value']['#title'] = $this->t('Start');

    $element['end_value'] = [
      '#title' => $this->t('End'),
    ] + $element['value'];

    if ($items[$delta]->start_date) {
      /** @var \Drupal\Core\Datetime\DrupalDateTime $start_date */
      $start_date = $items[$delta]->start_date;
      $element['value']['#default_value'] = $this->createDefaultValue($start_date, $element['value']['#date_timezone']);
    }

    if ($items[$delta]->end_date) {
      /** @var \Drupal\Core\Datetime\DrupalDateTime $end_date */
      $end_date = $items[$delta]->end_date;
      $element['end_value']['#default_value'] = $this->createDefaultValue($end_date, $element['end_value']['#date_timezone']);
    }

    return $element;
  }

  /**
   * {@inheritdoc}
   */
  public function massageFormValues(array $values, array $form, FormStateInterface $form_state) {
    // The widget form element type has transformed the value to a
    // DrupalDateTime object at this point. We need to convert it back to the
    // storage timezone and format.
    foreach ($values as &$item) {
      if (!empty($item['value']) && $item['value'] instanceof DrupalDateTime) {
        /** @var \Drupal\Core\Datetime\DrupalDateTime $start_date */
        $start_date = $item['value'];
        switch ($this->getFieldSetting('datetime_type')) {
          case DateRangeItem::DATETIME_TYPE_DATE:
            // If this is a date-only field, set it to the default time so the
            // timezone conversion can be reversed.
            datetime_date_default_time($start_date);
            $format = DATETIME_DATE_STORAGE_FORMAT;
            break;

          case DateRangeItem::DATETIME_TYPE_ALLDAY:
            // All day fields start at midnight on the starting date, but are
            // stored like datetime fields, so we need to adjust the time.
            // This function is called twice, so to prevent a double conversion
            // we need to explicitly set the timezone.
            $start_date->setTimeZone(timezone_open(drupal_get_user_timezone()));
            $start_date->setTime(0, 0, 0);
            $format = DATETIME_DATETIME_STORAGE_FORMAT;
            break;

          default:
            $format = DATETIME_DATETIME_STORAGE_FORMAT;
            break;
        }
        // Adjust the date for storage.
        $start_date->setTimezone(new \DateTimezone(DATETIME_STORAGE_TIMEZONE));
        $item['value'] = $start_date->format($format);
      }

      if (!empty($item['end_value']) && $item['end_value'] instanceof DrupalDateTime) {
        /** @var \Drupal\Core\Datetime\DrupalDateTime $end_date */
        $end_date = $item['end_value'];
        switch ($this->getFieldSetting('datetime_type')) {
          case DateRangeItem::DATETIME_TYPE_DATE:
            // If this is a date-only field, set it to the default time so the
            // timezone conversion can be reversed.
            datetime_date_default_time($end_date);
            $format = DATETIME_DATE_STORAGE_FORMAT;
            break;

          case DateRangeItem::DATETIME_TYPE_ALLDAY:
            // All day fields end at midnight on the end date, but are
            // stored like datetime fields, so we need to adjust the time.
            // This function is called twice, so to prevent a double conversion
            // we need to explicitly set the timezone.
            $end_date->setTimeZone(timezone_open(drupal_get_user_timezone()));
            $end_date->setTime(23, 59, 59);
            $format = DATETIME_DATETIME_STORAGE_FORMAT;
            break;

          default:
            $format = DATETIME_DATETIME_STORAGE_FORMAT;
            break;
        }
        // Adjust the date for storage.
        $end_date->setTimezone(new \DateTimezone(DATETIME_STORAGE_TIMEZONE));
        $item['end_value'] = $end_date->format($format);
      }
    }

    return $values;
  }

  /**
   * #element_validate callback to ensure that the start date <= the end date.
   *
   * @param array $element
   *   An associative array containing the properties and children of the
   *   generic form element.
   * @param \Drupal\Core\Form\FormStateInterface $form_state
   *   The current state of the form.
   * @param array $complete_form
   *   The complete form structure.
   */
  public function validateStartEnd(array &$element, FormStateInterface $form_state, array &$complete_form) {
    $start_date = $element['value']['#value']['object'];
    $end_date = $element['end_value']['#value']['object'];

    if ($start_date instanceof DrupalDateTime && $end_date instanceof DrupalDateTime) {
      if ($start_date->format('U') !== $end_date->format('U')) {
        $interval = $start_date->diff($end_date);
        if ($interval->invert === 1) {
          $form_state->setError($element, $this->t('The @title end date cannot be before the start date', ['@title' => $element['#title']]));
        }
      }
    }
  }

  /**
   * Creates a date object for use as a default value.
   *
   * This will take a default value, apply the proper timezone for display in
   * a widget, and set the default time for date-only fields.
   *
   * @param \Drupal\Core\Datetime\DrupalDateTime $date
   *   The UTC default date.
   * @param string $timezone
   *   The timezone to apply.
   *
   * @return \Drupal\Core\Datetime\DrupalDateTime
   *   A date object for use as a default value in a field widget.
   */
  protected function createDefaultValue($date, $timezone) {
    // The date was created and verified during field_load(), so it is safe to
    // use without further inspection.
    if ($this->getFieldSetting('datetime_type') == DateTimeItem::DATETIME_TYPE_DATE) {
      // A date without time will pick up the current time, use the default
      // time.
      datetime_date_default_time($date);
    }
    $date->setTimezone(new \DateTimeZone($timezone));
    return $date;
  }

}

Now I just gotta find a how to remove the seconds from the field...
Note:

You need to install Date Range
Flush the Cache
Enable the module
Select Time Range in the Form display settings, not the field settings.