def __init__(self, commit_number_log):

        # generate the symbol_map for more customization
        self.symbol_map = {
            'unknown': '-',
            'more': '+',
            'empty': '0',
        }
        one_to_ten = [str(x) for x in range(0, 10)]
        number_dict = zip(one_to_ten, one_to_ten)
        self.symbol_map.update(number_dict)
        self.commit_log = commit_number_log
commit_number_log should be in form of:
dataset/ETHPy150Open littleq0903/git-calendar/git_calendar/utils.py/GitCalendar.__init__