Generate a function parameters (args, kwargs) from strings by converting it with called function signature

introspect.py

from inspect import signature
import copy


def expected(key, sign):
    for el in sign.parameters.values():
        if key in el.name:
            return True
    return False


def cast(key, sign):
    for el in sign.parameters.values():
        if key in el.name:
            return el.annotation


def generate_signature(command, params, sign):
    kwargs = {}
    cleaned_params = copy.deepcopy(params)
    for index, param in enumerate(params):
        try:
            key, value = param.split("=")
        except ValueError:
            continue
        if expected(key, sign):
            kwargs.update({key: cast(key, sign)(value)})
            cleaned_params.remove(param)
        else:
            raise TypeError(
                "{cmd}() got an unexpected keyword argument '{param}'".format(
                    cmd=command, param=key))
    if len(cleaned_params) + len(kwargs) == len(sign.parameters.values()):
        return cleaned_params, kwargs

    args = []
    result = []
    for el in sign.parameters.values():
        if el.name not in kwargs:
            args.append(el)

    if len(args) == 1:
        if args[0].annotation is list:
            result.append(cleaned_params)
        else:
            result.extend(cleaned_params)
    return result, kwargs


class TestClass:

    def add(arg1 : str, arg2 : str, expire : int=0, noreply : bool=True):
        print(arg1)
        print(arg2)
        print(expire)
        print(noreply)

    def get_many(arg1 : list, expire : int=0, noreply : bool=True):
        print(arg1)
        print(expire)
        print(noreply)

    def fail(arg1 : int, expire : int=0, noreply : bool=True):
        print(arg1)
        print(expire)
        print(noreply)


test_add = "add test value expire=1 noreply=True"

extract = test_add.split()
print(extract)


obj = TestClass
sign = signature(obj.add)
print(sign.parameters.values())
args, kwargs = generate_signature(extract[0], extract[1:], sign)
obj.add(*args, **kwargs)
sign = signature(obj.get_many)
print(sign.parameters.values())
args, kwargs = generate_signature(extract[0], extract[1:], sign)
obj.get_many(*args, **kwargs)
sign = signature(obj.fail)
print(sign.parameters.values())
args, kwargs = generate_signature(extract[0], extract[1:], sign)
obj.fail(*args, **kwargs)