Why result of pyserial readlines, when no new data, is not empty list?

Question

I met some problem with pyserial (v3.4) readlines function.

when I run some test codes in IDLE of python 3.5

>>> import serial
>>> ser = serial.Serial('com4', timeout=1)
>>> a = ser.readlines()
>>> a
[]

but when I use the compare "is []", it give me a False

>>> a is []
False

and when I use the compare "== []", it give me a True

>>> a == []
True

I don't understand why that can happen. Is there any way to fix this, or not?

If you could, please help me with this problem.

Thank you very much.

---

Thank for Jim Fasarakis Hilliard, I have known how to edit the code and make it beautiful in PIP8. I edit and add new code for someone who meet the same problem with me

>>> import serial
>>> ser = serial.Serial('com4', timeout=1)
>>> a = ser.readlines()
>>> if not a:
        DO SOMETHING WHAT YOU WANT