'Given a section name, push it on the top of the stack.
Returns:
The new section, or None if there is no such section.'

def PushSection(self, name):

    if (name == '@'):
        new_context = self.stack[(-1)].context
    else:
        new_context = self.stack[(-1)].context.get(name)
    self.stack.append(_Frame(new_context))
    return new_context
