[Python] When are variables created? When will class instances be erased?

Variables are created when the file is imported.

An instance of the class is destroyed when the function finishes.

class A:
    def __init__(self):
        self.a = 'a'
        self.b = 'b'

    def __del__(self):
        print(self.__dict__)
        
def main():
    a = A()
    
main()
-> {'a': 'a', 'b': 'b'}

__del__ is executed when the class instance is destroyed. (main () is executed, and when the process is finished, the instance is destroyed and print is executed.)