Lists all the outputs in the symbol.

        Example
        -------
        >>> a = mx.sym.var('a')
        >>> b = mx.sym.var('b')
        >>> c = a + b
        >>> c.list_outputs()
        ['_plus12_output']

        Returns
        -------
        list of str
            List of all the outputs.
            For most symbols, this list contains only the name of this symbol.
            For symbol groups, this is a list with the names of all symbols
            in the group.

def list_outputs(self):
        """Lists all the outputs in the symbol.

        Example
        -------
        >>> a = mx.sym.var('a')
        >>> b = mx.sym.var('b')
        >>> c = a + b
        >>> c.list_outputs()
        ['_plus12_output']

        Returns
        -------
        list of str
            List of all the outputs.
            For most symbols, this list contains only the name of this symbol.
            For symbol groups, this is a list with the names of all symbols
            in the group.
        """
        size = ctypes.c_uint()
        sarr = ctypes.POINTER(ctypes.c_char_p)()
        check_call(_LIB.MXSymbolListOutputs(
            self.handle, ctypes.byref(size), ctypes.byref(sarr)))
        return [py_str(sarr[i]) for i in range(size.value)]