<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def clear(self, username, project):
 """Clear the cache for given project."""

        method = 'DELETE'
        url = ('/project/{username}/{project}/build-cache?'
               'circle-token={token}'.format(username=username,
                                             project=project,
                                             token=self.client.api_token))
        json_data = self.client.request(method, url)
        return json_data