String Object Representation in Python
This question already has an answer here:
__str__ (usually read dunder, for double under) is an instance method that is called whenever you run str(<object>) and returns the string representation of the object.
str(foo) acts as a function trying to convert foo into a string.
Note:
There is also a __repr__() method which is fairly similar to __str__() , the main difference being __repr__ should return an unambiguous string and __str__ is for a readable string. For a great response on the diffences between the two I'd suggest giving this answer a read.
__str__() is a magic instance method that doee this: when you print a class instance variable with print() , it will give you a string that can be modified by changing the returned string in the __str__() method. There's probably a better explanation to it but I can show you with code:
class Thing:
def __init__(self):
pass
def __str__(self):
return "What do you want?" #always use return
a = Thing()
print(a)
OUTPUT:
What do you want?
str() just converts a variable into a string type variable.
print(str(12.0))
OUTPUT:
'12.0'
You can confirm it is a string using the type() function.
print(type(str(12.)))
I don't know the exact output of that but it will peobably have 'str' in it.
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