URL: https://docs.python.org/2/tutorial/controlflow.html#pass-statements

Quoted verbatim:
"""
The pass statement does nothing. It can be used when a statement is required syntactically but the program requires no action. For example:
>>>

>>> while True:
...     pass  # Busy-wait for keyboard interrupt (Ctrl+C)
...

"""

While the example illustrates the point, it *may* give bad ideas to novice programmers reading it - "while True: pass" is an antipattern as it's very inefficient.