Bugs in importing when Deploying a LangChain web app to multiple hosting platforms! 
Labels: name: area: memory, name: auto:bug

### System Info

I have observed that while using the command belonging to importing "langchain.llms (for example as in from langchain.llms import HuggingFaceHub") have no problem when I deploy my web app to multiple hosting  sites like streamlit, Render, Heroku etc. 
However, using the "langchain.memory" as in from langchain.memory import ConversationBufferMemory
and "langchain.prompts" as in from langchain.prompts import PromptTemplate
causes deployment to fail in all said hosting sites. They throw a module not found error for the langchain.memory and langchain.prompts. 
Please note: that running in google colab or vscode does not have this error. 
Also, python version and langchain versions are irrelevant to this problem since I have tested through a lot of variations. 
Please help out. Thanks in advance

### Who can help?

@hwchase17
@agola11
@eyurtsev

### Information

- [X] The official example notebooks/scripts
- [ ] My own modified scripts

### Related Components

- [ ] LLMs/Chat Models
- [ ] Embedding Models
- [X] Prompts / Prompt Templates / Prompt Selectors
- [ ] Output Parsers
- [ ] Document Loaders
- [ ] Vector Stores / Retrievers
- [X] Memory
- [ ] Agents / Agent Executors
- [ ] Tools / Toolkits
- [ ] Chains
- [ ] Callbacks/Tracing
- [ ] Async

### Reproduction

import soundfile as sf
from langchain.llms import HuggingFaceHub

# Below line gives error not in vscode or google colab but in deployment to render, heroku, streamlit and other hosting sites as well. I have not used ConversationBufferMemory in below code even, since the this line causes problem even in initial importing
from langchain.memory import ConversationBufferMemory 

import speech_recognition as sr
# Initialize any API keys that are needed
import os
from flask import Flask, render_template, request, session, flash, get_flashed_messages

os.environ["HUGGINGFACEHUB_API_TOKEN"] = "write your own api here"
    
app = Flask(__name__)
app.secret_key = '123'
@app.route("/LLMEXP", methods=['GET', 'POST'])
def llmexp():
    if 'chat_messages' not in session:
        session['chat_messages'] = []

    conversation = HuggingFaceHub(repo_id="google/flan-t5-small", model_kwargs={"temperature": 0.1, "max_length": 256})

    if request.method == 'POST':
        if 'record_audio' in request.form:
            # Record audio and convert to text
            user_input = request.form['user_input']
        else:
            # User input from textarea
            user_input = request.form['user_input']

        if not user_input or user_input.isspace():
            flash("Please provide a valid input.")
            
        else:
            user_message = {'role': 'user', 'content': f"User: {user_input}"}
            session['chat_messages'].append(user_message)

            response = conversation(user_input)

            if not response.strip():
                response = "I didn't understand the question."

            #text_to_speech(response)

            assistant_message = {'role': 'assistant', 'content': f"Bot: {response}"}
            session['chat_messages'].append(assistant_message)

            session.modified = True

    return render_template("index.html", chat_messages=session['chat_messages'])

if __name__ == "__main__":
    app.run(debug=True)

### Expected behavior

I expect that I do not receive any error related to  "langchain.memory" or "langchain.prompts" error while deploying to a hosting site.