Convert a string of a fully qualified function, class or module into its correspong python object, if such exists. See examples at the end.

str2func.py

import sys
def str2func(name):
    "Convert a string of a fully qualified function, class or module into its python object"
    if isinstance(name, str):
        subpaths = name.split('.')
    else:
        return None
    
    module = subpaths.pop(0)
    if module in sys.modules:
        obj = sys.modules[module]
    else:
        return None
    
    for subpath in subpaths:
        obj = getattr(obj, subpath, None)
        if obj == None: 
            return None
        
    return obj

import fastai.gen_doc.doctest
print(str2func('fastai.gen_doc.doctest.this_tests'))

import numpy
print(str2func('numpy.core.fromnumeric.any'))
print(str2func('numpy.core'))

import inspect
print(str2func('inspect.ismodule'))
print(str2func('inspect.doesnotexist'))
print(str2func('doesnotexist'))

# prints
# 
# <function this_tests at 0x7f25067aa1e0>
# <function any at 0x7f250426eae8>
# <module 'numpy.core' from '.../python3.7/site-packages/numpy/core/__init__.py'>
# <function ismodule at 0x7f25194d80d0>
# None
# None