PS D:\python> python
Python 3.9.6 (tags/v3.9.6:db3ff76, Jun 28 2021, 15:26:21) [MSC v.1929 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> abc.py
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'abc' is not defined
>>> abc.py
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'abc' is not defined
>>> aa.py
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'aa' is not defined
>>>

 mấy anh cho em hỏi lỗi này là lỗi gì và cách fix thế nào ạ