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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 add_features(host_name, client_name, client_pass, feature_names):
 """ Add a number of numerical features in the client. Inputs: - host_name: A string containing the address of the machine where the PServer instance is hosted. - client_name: The PServer client name. - client_pass: The PServer client's password. - feature_names: A python list of feature names. """

    init_feats = ("&".join(["%s=0"]*len(feature_names))) % tuple(feature_names)
    features_req = construct_request("pers",
                                     client_name,
                                     client_pass,
                                     "addftr",
                                     init_feats)
    send_request(host_name,
                 features_req)