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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 fast_sync_fetch(working_dir, import_url):
 """ Get the data for an import snapshot. Store it to a temporary path Return the path on success Return None on error """

    try:
        fd, tmppath = tempfile.mkstemp(prefix='.blockstack-fast-sync-', dir=working_dir)
    except Exception, e:
        log.exception(e)
        return None
    
    log.debug("Fetch {} to {}...".format(import_url, tmppath))

    try:
        path, headers = urllib.urlretrieve(import_url, tmppath)
    except Exception, e:
        os.close(fd)
        log.exception(e)
        return None
    
    os.close(fd)
    return tmppath