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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 file_or_token(value):
 """ If value is a file path and the file exists its contents are stripped and returned, otherwise value is returned. """

    if isfile(value):
        with open(value) as fd:
            return fd.read().strip()

    if any(char in value for char in '/\\.'):
        # This chars will never be in a token value, but may be in a path
        # The error message will be handled by the parser
        raise ValueError()

    return value