import string


def generate_letter_number_list():
    # spreadsheet style column names A-Z, AA-AB-ZZ, AAA-AAB-ZZZ, etc.
    result = [letter for letter in string.ascii_uppercase]
    for letter in string.ascii_uppercase:
        for letter2 in string.ascii_uppercase:
            result.append(f"{letter}{letter2}")
    return result


class NameGenerator:
    def __init__(self, N, M):
        self.COLNAMES = generate_letter_number_list()
        self.Col = lambda x: self.COLNAMES[x]
        self.N = N
        self.M = M

    def get_name(self, cell):
        return f"{self.Col(cell[0])}{self.M - cell[1]}"


if __name__ == "__main__":
    name_generator = NameGenerator()
    cell = (100, 200)
    print(name_generator.get_name(cell))