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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 NCBISequenceLinkURL(title, default=None):
 """ Given a sequence title, like "gi|42768646|gb|AY516849.1| Homo sapiens", return the URL of a link to the info page at NCBI. title: the sequence title to produce a link URL for. default: the value to return if the title cannot be parsed. """

    try:
        ref = title.split('|')[3].split('.')[0]
    except IndexError:
        return default
    else:
        return 'http://www.ncbi.nlm.nih.gov/nuccore/%s' % (ref,)