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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def valid_state(state: str) -> bool: """Validate State Argument Checks that either 'on' or 'off' was entered as an argument to the CLI and make it lower case. :param state: state to validate. :returns: True if state is valid. .. versionchanged:: 0.0.12 This moethod was renamed from validateState to valid_state to conform to PEP-8. Also removed "magic" text for state and instead reference the _VALID_STATES constant. """

    lower_case_state = state.lower()

    if lower_case_state in _VALID_STATES:
        return True
    return False