import csv


def read_csv(filename):
    """
    Reads data from a csv file.
    Note: first line is reserved for header, so it is ignored.

    :param filename: name of the data file.
    :return: data in a list structure.
    """
    with open(filename, 'r') as _input_file:
        return list(list(row) for row in csv.reader(_input_file, delimiter=' '))[1:]