def METHOD_NAME(orig_key):
    key = orig_key.strip()
    key = key.replace("-", "_")  # Our _client lib wants "_" in place of "-"
    # Convert camelCase to snake_case
    key = SNAKE1.sub(r'\1_\2', key)
    key = SNAKE2.sub(r'\1_\2', key).lower()
    if key not in SUPPORTED_KEYS:
        raise Exception("unknown constraint in %s" % orig_key)
    return key