Indices in Python list

You may feel uncomfortable with Python indices at the beginning. But it is really convenient if you understand it. You'd love its simplicity actually:

>>> a = list(range(10))
>>> a
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
>>> a[::2]
[0, 2, 4, 6, 8]
>>> a[1::2]
[1, 3, 5, 7, 9]
>>> a[::-2]
[9, 7, 5, 3, 1]
>>> a[1::-2]
[1]
>>> a[1:8]
[1, 2, 3, 4, 5, 6, 7]
>>> a[1:-2]
[1, 2, 3, 4, 5, 6, 7]
>>> a[::-1]
[9, 8, 7, 6, 5, 4, 3, 2, 1, 0]
>>> a[100]
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
IndexError: list index out of range
>>> a[:100]
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
>>> a[7:100]
[7, 8, 9]

Reference:

https://docs.python.org/3/tutorial/introduction.html#strings