the ever continuing struggle to load a .py file as a module without deprecation warnings

gistfile1.py

import sys

def load_py_file(path):
    if sys.version_info >= (3, 4):
        """???? what goes here ????
        load_module() is deprecated?  Docs at
        https://docs.python.org/3.4/library/importlib.html#importlib.abc.Loader.load_module
        https://docs.python.org/3.4/library/importlib.html#importlib.abc.Loader.exec_module
        completely unclear, what does "exec_module()" do?   is that the replacement?
        can we please stop changing the API here?"""
    elif sys.version_info >= (3,3):
        from importlib import machinery
        return machinery.SourceFileLoader("plugin_base", path).load_module()
    else:
        # "imp" is deprecated in 3.3
        import imp
        return imp.load_source("plugin_base", path)

load_py_file("test2.py")