'Low level method to expands the template piece by piece.
Args:
data_dict: The JSON data dictionary.
callback: A callback which should be called with each expanded token.
Example: You can pass \'f.write\' as the callback to write directly to a file
handle.'

def render(self, data_dict, callback):

    context = _ScopedContext(data_dict, self.undefined_str)
    _Execute(self._program.Statements(), context, callback)
