Given a Selector and Filter, return True if the Selector is
        compatible with the given Filter, and False if they contradict.

def is_applicable_selector(selector, filter):
    """ Given a Selector and Filter, return True if the Selector is
        compatible with the given Filter, and False if they contradict.
    """
    for test in selector.allTests():
        if not test.isCompatible(filter.tests):
            return False
    
    return True