for attr in attrs:
    name, value = attr
    if name == 'name' or name=='value':
        self.tmp.append([name, value])
        print([name, value]
self.get.append(self.tmp)
print(self.get)

#вывод
['name', '_username']
['value', '']
[<class 'object'>, [['name', '_username'], ['value', '']]]