8.6: The __str__ Method
- Page ID
- 15465
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__str__ is a special method, like __init__, that is supposed to return a string representation of an object.
For example, here is a str method for Time objects:
# inside class Time:
def __str__(self):
return '%.2d:%.2d:%.2d' % (self.hour, self.minute, self.second)
When you print an object, Python invokes the str method:
>>> time = Time(9, 45) >>> print time 09:45:00
When I write a new class, I almost always start by writing __init__, which makes it easier to instantiate objects, and __str__, which is useful for debugging.
Exercise \(\PageIndex{1}\)
Write a str method for the Point class. Create a Point object and print it.