How can I append a None value to a list in Python?

问题

I have a list :

A = ['Yes']

I want to have

A = ['Yes',None]

How can I do this?

回答1:

Just use append:

A.append(None)

>>> print A
['Yes', None]

回答2:

Simple:

A.append(None)

or

A += [None]

or

A.extend([None])

or

A[len(A):] = [None]

来源：https://stackoverflow.com/questions/23238489/how-can-i-append-a-none-value-to-a-list-in-python