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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 build_url(self):
 """Builds the URL for elevations API services based on the data given by the user. Returns: url (str):
 URL for the elevations API services """

        url = '{protocol}/{url}/{rest}/{version}/{restapi}/{rscpath}/' \
              '{query}'.format(protocol=self.schema.protocol,
                               url=self.schema.main_url,
                               rest=self.schema.rest,
                               version=self.schema.version,
                               restapi=self.schema.restApi,
                               rscpath=self.schema.resourcePath,
                               query=self.schema.query)
        return url.replace('/None/', '/')