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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 validate_timeout_or_zero(option, value):
 """Validates a timeout specified in milliseconds returning a value in floating point seconds for the case where None is an error and 0 is valid. Setting the timeout to nothing in the URI string is a config error. """

    if value is None:
        raise ConfigurationError("%s cannot be None" % (option, ))
    if value == 0 or value == "0":
        return 0
    return validate_positive_float(option, value) / 1000.0