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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 get_proxy_url(self, pgt):
 """Returns proxy url, given the proxy granting ticket"""

        params = urllib_parse.urlencode({'pgt': pgt, 'targetService': self.service_url})
        return "%s/proxy?%s" % (self.server_url, params)