def get_name():
    fname = input('Enter your first name, please:')
    lname = input('Enter your last name, please:')
    return (fname, lname)

import BB

BB.get_name()

print(__name__)

yuval> ls -l x.py 
-rw-rw-r-- 1 yuval yuval 15 Oct 23 18:23 x.py
yuval> python3 x.py 
__main__
yuval> 
yuval> python3
Python 3.8.5 (default, Sep  9 2020, 11:29:34) 
[GCC 9.3.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import x
x
>>> 

def get_name():
    fname = input('Enter your first name, please:')
    lname = input('Enter your last name, please:')
    return (fname, lname)

if __name__ == '__main__':  # so if BB is the main module
    names = get_name()
    print(f'first name is: {names[0]}, last name is {names[1]}.')

>>> import sys
>>> sys.path
['', '/usr/local/lib/python38.zip', '/usr/local/lib/python3.8', '/usr/local/lib/python3.8/lib-dynload', '/home/yuval/.local/lib/python3.8/site-packages', '/usr/local/lib/python3.8/site-packages']
>>> 

>>> import AA
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/yuval/Documents/languages/python/progs/module_import/AA.py", line 1, in <module>
    import module_import.BB
ModuleNotFoundError: No module named 'module_import'
>>> 

>>> dir()
['__annotations__', '__builtins__', '__doc__', '__loader__', '__name__', '__package__', '__spec__', 'sys']
>>> 
>>> dir(sys)
['__breakpointhook__', '__displayhook__', '__doc__', '__excepthook__', '__interactivehook__', '__loader__', '__name__', '__package__', '__spec__', '__stderr__', '__stdin__', '__stdout__', '__unraisablehook__', '_base_executable', '_clear_type_cache', '_current_frames', '_debugmallocstats', '_framework', '_getframe', '_git', '_home', '_xoptions', 'abiflags', 'addaudithook', 'api_version', 'argv', 'audit', 'base_exec_prefix', 'base_prefix', 'breakpointhook', 'builtin_module_names', 'byteorder', 'call_tracing', 'callstats', 'copyright', 'displayhook', 'dont_write_bytecode', 'exc_info', 'excepthook', 'exec_prefix', 'executable', 'exit', 'flags', 'float_info', 'float_repr_style', 'get_asyncgen_hooks', 'get_coroutine_origin_tracking_depth', 'getallocatedblocks', 'getcheckinterval', 'getdefaultencoding', 'getdlopenflags', 'getfilesystemencodeerrors', 'getfilesystemencoding', 'getprofile', 'getrecursionlimit', 'getrefcount', 'getsizeof', 'getswitchinterval', 'gettrace', 'hash_info', 'hexversion', 'implementation', 'int_info', 'intern', 'is_finalizing', 'maxsize', 'maxunicode', 'meta_path', 'modules', 'path', 'path_hooks', 'path_importer_cache', 'platform', 'prefix', 'ps1', 'ps2', 'pycache_prefix', 'set_asyncgen_hooks', 'set_coroutine_origin_tracking_depth', 'setcheckinterval', 'setdlopenflags', 'setprofile', 'setrecursionlimit', 'setswitchinterval', 'settrace', 'stderr', 'stdin', 'stdout', 'thread_info', 'unraisablehook', 'version', 'version_info', 'warnoptions']
>>>