def read(in_path):
    """ Read a grp file at the path specified by in_path.

    Args:
        in_path (string): path to GRP file

    Returns:
        grp (list)

    """
    assert os.path.exists(in_path), "The following GRP file can't be found. in_path: {}".format(in_path)

    with open(in_path, "r") as f:
        lines = f.readlines()
        # need the second conditional to ignore comment lines
        grp = [line.strip() for line in lines if line and not re.match("^#", line)]

    return grp
Read a grp file at the path specified by in_path.

    Args:
        in_path (string): path to GRP file

    Returns:
        grp (list)