def parse_im_line(line):
    """Parse comma-separated values for isotope masses from line."""
    fields = line.split(',')
    Z = int(fields[0])
    A = int(fields[1])
    symbol = fields[2].strip()
    mass = float(fields[3])
    mass_unc = float(fields[4])
    estimated_flag = fields[5].strip()
    return Z, A, symbol, mass, mass_unc, estimated_flag
