def _block_shape(values, ndim=<NUM_LIT:1>, shape=None):
if values.ndim < ndim:<EOL><INDENT>if shape is None:<EOL><INDENT>shape = values.shape<EOL><DEDENT>if not is_extension_array_dtype(values):<EOL><INDENT>values = values.reshape(tuple((<NUM_LIT:1>, ) + shape))<EOL><DEDENT><DEDENT>return values<EOL>
guarantee the shape of the values to be at least 1 d