Added automatic requirements installation from docstring

[DarkIceXD]

This makes it so that the requirements in the python docstring get installed before executing the pipeline. Fixes #151 .
The process goes like:

• load python file
• parse using ast
• get the docstring from ast
• find the requirements section in the docstring using regex (re)
• create a process using subprocess.Popen and pip install the dependencies

Everything gets done before the script executes for the first time.

To test this:

• first run pip uninstall numpy
• then add this test.py to your pipelines directory or upload using swagger UI (http://localhost:9099/docs)

"""
title: Test pipline
requirements: numpy
"""

from typing import List, Union, Generator, Iterator
import numpy

class Pipeline:
    def __init__(self):
        print(numpy)
    
    def pipe(
        self, user_message: str, model_id: str, messages: List[dict], body: dict
    ) -> Union[str, Generator, Iterator]:
        return "hello world"

[Marenz]

Looks nice. How does it behave in case a dependency isn't found or some other error?

Sidenote: there is the uv pip drop-in alternative which is (without exaggeration) x10 faster, if there would be an option to use it instead, that would be awesome. Though make it configurable might be a bit extra work.

[Marenz]

Yeah, that is def. better now

[DarkIceXD]

Looks nice. How does it behave in case a dependency isn't found or some other error?

it doesnt care. notice line 130 one could change the _, _ = ... to stdout, stderr = ... and get the output or get the return code from the process but i figured that we might as well try to run the script anyway and see if it fails (right now it just runs the script with missing dependencies aswell).

Sidenote: there is the uv pip drop-in alternative which is (without exaggeration) x10 faster, if there would be an option to use it instead, that would be awesome. Though make it configurable might be a bit extra work.

i never used it. we could add uv in the requirements.txt and then just use uv pip. are there any drawbacks?

[DarkIceXD]

also i could remove line 84-105 and line 120-124 in start.sh as it isnt needed anymore once the pull request gets merged