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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 exists(self, uri):
 """Method returns true is the entity exists in the Repository, false, otherwise Args: uri(str):
 Entity URI Returns: bool """

        ##entity_uri = "/".join([self.base_url, entity_id])
        try:
            urllib.request.urlopen(uri)
            return True
        except urllib.error.HTTPError:
            return False