def get_forwards_dict(forwards_file):
    """Returns a dictionary with new ott_ids for forwarded ott_ids
    """
    fwd_dict = {}
    fi=open(forwards_file)
    header = fi.readline()
    for lin in fi:
        lii = lin.split()
        fwd_dict[int(lii[0])]=lii[1]
    return fwd_dict