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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def add_gtc_header_table_row(t, telpars):
 """ Add a row with current values to GTC table Arguments --------- t : `~astropy.table.Table` The table to append row to telpars : list list returned by server call to getTelescopeParams """

    now = Time.now().mjd
    hdr = create_header_from_telpars(telpars)

    # make dictionary of vals to put in table
    vals = {k: v for k, v in hdr.items() if k in VARIABLE_GTC_KEYS}
    vals['MJD'] = now
    # store LST as hourangle
    vals['LST'] = Longitude(vals['LST'], unit=u.hour).hourangle
    t.add_row(vals)