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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 tvdb_refresh_token(token):
 """ Refreshes JWT token Online docs: api.thetvdb.com/swagger#!/Authentication/get_refresh_token= """

    url = "https://api.thetvdb.com/refresh_token"
    headers = {"Authorization": "Bearer %s" % token}
    status, content = _request_json(url, headers=headers, cache=False)
    if status == 401:
        raise MapiProviderException("invalid token")
    elif status != 200 or not content.get("token"):
        raise MapiNetworkException("TVDb down or unavailable?")
    return content["token"]