def METHOD_NAME(self, high_nibble):
    """
    Check if the passed nibble matches any of the control flags.
    The flags are assumed to be in the lower half of each self.flags byte.
    Returns index or False
    """
    for idx, byte in enumerate(self.flags):
        # The game compares with the entire byte, not just the lower nibble of the flag
        nbl = byte
        if nbl == high_nibble:
            return idx
    return False