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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_asset_spatial_session(self, proxy):
 """Gets the session for retrieving spatial coverage of an asset. arg proxy (osid.proxy.Proxy):
 a proxy return: (osid.repository.AssetSpatialSession) - an AssetSpatialSession raise: OperationFailed - unable to complete request raise: Unimplemented - supports_spatial_assets() is false compliance: optional - This method must be implemented if supports_spatial_assets() is true. """

        if not self.supports_spatial_asset():
            raise Unimplemented()
        try:
            from . import sessions
        except ImportError:
            raise  # OperationFailed()
        proxy = self._convert_proxy(proxy)
        try:
            session = sessions.AssetSpatialSession(proxy, runtime=self._runtime)
        except AttributeError:
            raise  # OperationFailed()
        return session