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Kind-of True

See: truthiness in Python and Python truth value testing.

There are several places where you will find Python applying a test of True that is more general than simply val == True.

One example is in if statements:

>>> val = 'a string'  # A not-empty string is True for truth testing
>>> if val:
...     print('Truth testing of "val" returned True')
Truth testing of "val" returned True

Here the if val: clause applies Python truth value testing to 'a string', and returns True. This is because the truth value testing algorithm returns True from an not-empty string, and False from an empty string:

>>> another_val = ''
>>> if another_val:
...     print('No need for a message, we will not get here')

You can see the results of truth value testing using bool() in Python. For example:

>>> bool(True)
True
>>> bool(False)
False
>>> bool(['some', 'elements'])  # not-empty list tests as True
True
>>> bool([])  # an empty list tests as False
False
>>> bool(10)  # any number other than zero evaluates as True
True
>>> bool(1)
True
>>> bool(0)
False
>>> bool(None)  # None tests as False
False

Examples of situations in which Python uses truth value testing are if statements; while statements and assert statements.