How to properly create a parent class for multiple child classes?

Question

Python

Good afternoon. I have 3 child classes, each of which can call 3 identical methods. In the class constructor, the dictionary is being filled. But when I print out the dictionary, I find that each class contains data from all 3 classes. Tell me how to create classes correctly so that you don’t have to write 3 identical methods in each?
Example:

class CECommon:
    data = {}

    def get(self):
        return self.data

    def get_by_id(self, id, only_name=True):
        if id not in self.data:
            return False

        return self.data[id]['name'] if only_name else self.data[id]

    def search_by_name(self, name):
        return {k: val for k, val in self.data.items() if val['name'].lower().count(name.lower())}


class AAA(CECommon):
    def __init__(self, text):
        for row in text.splitlines():
            val = row.split(';')
            self.data[int(val[0])] = {
                'id': int(val[0]),
                'pos_id': int(val[1]),
                'name': val[2],
            }

        self.__data = dict(sorted(self.data.items(), key=lambda x: x[1]['name']))


class BBB(CECommon):
    def __init__(self, text):
        for row in text.splitlines():
            val = row.split(';')
            self.data[int(val[0])] = {
                'id': int(val[0]),
                'name': val[1],
            }

        self.__data = dict(sorted(self.data.items()))


class CCC(CECommon):
    def __init__(self, text):
        for row in text.splitlines():
            val = row.split(';')
            self.data[int(val[0])] = {
                'id': int(val[0]),
                'name': val[1],
            }

        self.__data = dict(sorted(self.data.items(), key=lambda x: x[1]['name']))

If you call ССС.get() (of course, after all 3 classes have been called before and filled with data), then we will get a dictionary with the data of all (AAA, BBB, CCC) classes