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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 delete_project_avatar(self, project, avatar):
 """Delete a project's avatar. :param project: ID or key of the project to delete the avatar from :param avatar: ID of the avatar to delete """

        url = self._get_url('project/' + project + '/avatar/' + avatar)
        return self._session.delete(url)