def prepare_update_sql(list_columns, list_values, data_code=100):
    """
    Creates a string for the update query
    :param list_columns: columns that are in need of an update
    :param list_values: values where the columns should be updated with
    :param data_code: data code to add to the columns
    :return: string with the columns and update values
    """
    string = ''
    for i in enumerate(list_columns):
        if list_values[i[0]] is not None:
            if len(i[1]) >= 50:
                new_label = i[1][:50] + '_' + str(data_code)
                string = string + '`' + new_label + '`' + '= ' + '\'' + str(list_values[i[0]]) + '\'' + ', '
            else:
                string = string + '`' + i[1] \
                         + '_' + str(data_code) + '`' + '= ' + '\'' + str(list_values[i[0]]) + '\'' + ', '
    string = string.replace("None", "Null")
    return string[:-2]