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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 formatted URL for the asset's File with serialized parameters. Usage: """


        url = self.fields(self._locale()).get('file', {}).get('url', '')
        args = ['{0}={1}'.format(k, v) for k, v in kwargs.items()]

        if args:
            url += '?{0}'.format('&'.join(args))

        return url