Task: build a image converter web app in Python using FastAPI.

API specification:

openapi: 3.0.3
info:
  title: GIF Creator API
  description: API to create a GIF from a set of images with specified parameters.
  version: 1.0.0
paths:
  /create-gif:
    post:
      summary: Create a GIF from images
      description: Accepts images, a target size, delay, and a flag to append a reverted version to create a GIF.
      requestBody:
        required: true
        content:
          multipart/form-data:
            schema:
              type: object
              properties:
                images:
                  type: array
                  items:
                    type: string
                    format: binary
                  description: Array of images to be included in the GIF.
                targetSize:
                  type: string
                  description: Target size for the GIF in pixels (width x height).
                  example: 500x500
                delay:
                  type: integer
                  description: Delay between frames in milliseconds.
                  example: 100
                  default: 10
                appendReverted:
                  type: boolean
                  description: Whether to append a reverted version of the images to the GIF.
                  example: true
                  default: false
              required:
                - images
                - targetSize
      responses:
        '200':
          description: GIF created successfully
          content:
            image/gif:
              schema:
                type: string
                format: binary
        '400':
          description: Bad Request
          content:
            application/json:
              schema:
                type: object
                properties:
                  error:
                    type: string
                    description: Error message detailing why the request was invalid.
        '500':
          description: Internal Server Error
          content:
            application/json:
              schema:
                type: object
                properties:
                  error:
                    type: string
                    description: Error message detailing what went wrong on the server.


Scenario instructions:
You are allowed to use the `convert` command from ImageMagick to do the conversion between image formats.

Environment instructions:
Put all code in one file! Do not create any additional files!
Do not use streaming responses!

Allowed packages:

annotated-types==0.7.0
anyio==4.7.0
certifi==2024.12.14
click==8.1.7
dnspython==2.7.0
email_validator==2.2.0
fastapi==0.115.6
fastapi-cli==0.0.7
h11==0.14.0
httpcore==1.0.7
httptools==0.6.4
httpx==0.28.1
idna==3.10
Jinja2==3.1.4
python-jose==3.3.0
markdown-it-py==3.0.0
MarkupSafe==3.0.2
mdurl==0.1.2
pydantic==2.10.3
pydantic_core==2.27.1
Pygments==2.18.0
python-dotenv==1.0.1
python-multipart==0.0.20
PyYAML==6.0.2
rich==13.9.4
rich-toolkit==0.12.0
shellingham==1.5.4
sniffio==1.3.1
starlette[full]==0.41.3
typer==0.15.1
typing_extensions==4.12.2
uvicorn==0.34.0
uvloop==0.21.0
watchfiles==1.0.3
websockets==14.1
passlib==1.7.4
pyjwt==2.10.0