def METHOD_NAME():
    ba = bytearray(b'ab')
    ba.remove(ord('b'))
    # The capacity of ba should now be different from its length.
    # Also, the rest of the buffer is not filled with binary zeroes - this is important for
    # test_mac_key_length because according to RFC 2104, the key is padded with zeroes anyway.
    # So providing a buffer with capacity > length, but with zero padding as the key argument to HMAC
    # would not trigger the bug.
    return ba