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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 optional(name, default) -> 'Wildcard': """Create a `Wildcard` that matches a single argument with a default value. If the wildcard does not match, the substitution will contain the default value instead. Args: name: The name for the wildcard. default: The default value of the wildcard. Returns: A n optional wildcard. """

        return Wildcard(min_count=1, fixed_size=True, variable_name=name, optional=default)