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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_last_modification_date(url):
 """Get the last modification date of the ontology."""

    request = requests.head(url)
    date_string = request.headers["last-modified"]
    parsed = time.strptime(date_string, "%a, %d %b %Y %H:%M:%S %Z")
    return datetime(*(parsed)[0:6])