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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_token(token):
 """Asserts a provided string is a valid duration token representation :param token: duration representation token :type token: string """

    is_scale = False

    # Check if the token represents a scale
    # If it doesn't set a flag accordingly
    try:
        Scale(token)
        is_scale = True
    except ScaleFormatError:
        pass

    # If token either represents a numerical value, a
    # separator token, or a scale, it is considered valid
    if any([token.isdigit(), token in SEPARATOR_TOKENS, is_scale]):
        return True

    return False