human
Solve the following python programming problem given the following code:
@ override_settings (WSGI_APPLICATION = None) 
def test_default(self) : 
    '
        If ``WSGI_APPLICATION`` is ``None``, the return value of
        ``get_wsgi_application`` is returned.

        ' 
    fake_app = object () 
    def mock_get_wsgi_app() : 
        return fake_app 
from django.core.servers import basehttp 
    _orig_get_wsgi_app = basehttp.get_wsgi_application 
    basehttp.get_wsgi_application = <MASK> 
    try : 
        app = get_internal_wsgi_application () 
        self.assertTrue ((app is fake_app)) 
finally : 
        basehttp.get_wsgi_application = _orig_get_wsgi_app 
    
    Given the code above, what is a proper replacement for <MASK>?
assistant
#Here is a proper replacement for <MASK>.
def mock_get_wsgi_app(