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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 olderado_best_model(pdb_id):
 """ Checks the Olderado web server and returns the most representative conformation for PDB NMR structures. Notes ----- Uses OLDERADO from the EBI. See http://www.ebi.ac.uk/pdbe/nmr/olderado/ and citations therein. Parameters pdb_id : str The 4-character PDB code for the NMR structure of interest. Returns ------- model_no : int The conformation number of the most-representative conformation. Raises ------ ValueError If the model number it finds is not an integer. This might indicate that the website format has changed. """

    pdb_code = pdb_id[:4].lower()
    olderado_url = 'http://www.ebi.ac.uk/pdbe/nmr/olderado/searchEntry?pdbCode=' + pdb_code
    olderado_page = download_decode(olderado_url, verbose=False)
    if olderado_page:
        parsed_page = BeautifulSoup(olderado_page, 'html.parser')
    else:
        return None
    try:
        best_model = parsed_page.find_all('td')[1]
    except IndexError:
        print("No model info could be found for {0} - ensure that it's an NMR structure.".format(pdb_id))
        return None
    try:
        model_no = int(best_model.string)
    except ValueError as v:
        print("Did not find a number for best model.")
        raise v
    return model_no