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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 calc_fringetime(d):
 """ Estimate largest time span of a "segment". A segment is the maximal time span that can be have a single bg fringe subtracted and uv grid definition. Max fringe window estimated for 5% amp loss at first null averaged over all baselines. Assumes dec=+90, which is conservative. Returns time in seconds that defines good window. """


    maxbl = d['uvres']*d['npix']/2    # fringe time for imaged data only
    fringetime = 0.5*(24*3600)/(2*n.pi*maxbl/25.)   # max fringe window in seconds
    return fringetime