you wont believe what this method does

def count_lines_in_file(self, fname=''):
        """ you wont believe what this method does """
        i = 0
        if fname == '':
            fname = self.fullname
        try:
            #with open(fname, encoding="utf8") as f:
            with codecs.open(fname, "r",encoding='utf8', errors='ignore') as f:    
                for i, _ in enumerate(f):
                    pass
            return i + 1    
        except Exception as ex:
            print('cant count lines in file in "', fname, '":', str(ex))
            return 0