I've seen the term __str__ used a lot within classes in Python. I've tried to look up what it means and its functions but many websites teach it in relation to the Java function toString or __repr__. As I don't come from a Java background, its hard for me to learn it that way. I've also seen people compare it to the function str() but I don't know how accurate that is or in what ways.
Could someone explain it to me in simple terms? Thanks.
When Python needs to convert a class instance to a string, it calls its __str__() method. If it doesn't have __str__() it falls back on __repr__(). If the class doesn't define either of these methods, it will normally inherit them from the object base class, which returns a string like <className object at 0x1234>
This is used by the str() function, as well as formatting methods like str.format(), the string % operator, and f-strings. So defining the __str__() method allows you to customize how objects in your class are displayed in messages.
Analogously, the repr() function calls the __repr__() method. This method is generally intended to return a string containing a representation more appropriate for debugging and/or parsing, rather than for end user display.
The __str__ magic method defines the string representation of an object.
Here is an example for a very boring class A:
>>> class A:
... pass
...
>>> str(A())
'<__main__.A object at 0x7fe249b93ac8>'
This is the default. It uses the built-in __str__ method inherited from object. For our class B, we're looking for a more individual approach:
>>> class B:
... def __str__(self):
... return "Something individual"
...
>>> str(B())
'Something individual'
If you're looking for the difference between __str__ and __repr__, have a look here Difference between __str__ and __repr__?
