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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 _parse_abbreviation(uri_link):
 """ Returns a team's abbreviation. A school or team's abbreviation is generally embedded in a URI link which contains other relative link information. For example, the URI for the New England Patriots for the 2017 season is "/teams/nwe/2017.htm". This function strips all of the contents before and after "nwe" and converts it to uppercase and returns "NWE". Parameters uri_link : string A URI link which contains a team's abbreviation within other link contents. Returns ------- string The shortened uppercase abbreviation for a given team. """

    abbr = re.sub(r'/[0-9]+\..*htm.*', '', uri_link('a').attr('href'))
    abbr = re.sub(r'/.*/schools/', '', abbr)
    abbr = re.sub(r'/teams/', '', abbr)
    return abbr.upper()