特殊メソッド

class Word(object):
    def __init__(self, text):
        self.text = text
    
    def __str__(self):
        return 'texttxet'
    
    def __len__(self):
        return len(self.text)
    
    def __add__(self, word):
        return self.text.lower() + word.text.lower()
    
    def __eq__(self, word):
        return self.text.lower == word.text.lower()

w = Word('aaaaaaaaaa')
w2 = Word('bbbbbbbbbbbbb')

print(w)
print(len(w))
print(w + w2)
print(w == w2)

実行結果

texttxet
10
aaaaaaaaaabbbbbbbbbbbbb
False