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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 url(self, **kwargs):
 """Returns a URL for the link with optional template expansion. If the link is marked as templated, the href will be expanded according to RFC6570, using template variables provided in the keyword arguments. If the href is a valid URI Template, but the link is not marked as templated, the href will not be expanded even if template variables are provided. """

        if self.is_templated:
            return uritemplate.expand(self.template, kwargs)
        else:
            return self.template