Return the file extension for an abi3-compliant Extension()

def get_abi3_suffix():
    """Return the file extension for an abi3-compliant Extension()"""
    for suffix, _, _ in (s for s in imp.get_suffixes() if s[2] == imp.C_EXTENSION):
        if '.abi3' in suffix:  # Unix
            return suffix
        elif suffix == '.pyd':  # Windows
            return suffix