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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 get_zipped_file(url, encoding_error_opt='ignore'):
 """Download and unzip the report file at the given URL. Downloads and unzips the CO-TRACER archive at the given URL. This is not intended for data outside of the CO-TRACER official site and it will automatically extract the first file found in the downloaded zip archive as the CO-TRACER website produces single file archives. Note that the contents of that file are loaded directly into memory. @param url: The URL to download the archive from. @type url: str @return: The contents of the first file found in the provided archive. @rtype: str """

    remotezip = urllib2.urlopen(url)
    raw_contents = cStringIO.StringIO(remotezip.read())
    target_zip = zipfile.ZipFile(raw_contents)
    first_filename = target_zip.namelist()[0]
    return unicode(target_zip.read(first_filename), errors=encoding_error_opt)