examples = {}
class Example():
def __init__(self, number: int) -> None:
self.number = number
def find_key(self, items: list) -> str:
for key, value in items:
if id(value) == id(self):
return key
examples[0] = Example(1)
examples[1] = Example(2)
items = list(examples.items())
print(examples[0].find_key(items))
print(examples[1].find_key(items))