How to use the validators.length function in validators

def test_returns_true_on_valid_length(value, min, max):
    assert validators.length(value, min=min, max=max)

def test_returns_failed_validation_on_invalid_range(value, min, max):
    assert isinstance(
        validators.length(value, min=min, max=max),
        validators.ValidationFailure
    )

def test_raises_assertion_error_for_invalid_args(value, min, max):
    with pytest.raises(AssertionError):
        assert validators.length(value, min=min, max=max)

def request_form(hash_map):
    """
    """
    form = request.form
    
    message = None
    name = form['name']
    hash_map['name'] = name
    hash_map['value'] = {}
    
    if not length(name, 2, 20):
        message = 'nada 1'
    elif not username(name):
        message = 'nada 2'
    
    list_label = [ int(x.split('_')[3]) for x in form if x.startswith('label_name_') ]
    
    if len(list_label) > 0:    
        len_label = max(list_label) + 1
        for i in range(len_label):
            
            i = str(i)
            if 'label_name_'+g.lan+'_'+i in form:
                key = form['label_name_'+g.lan+'_'+i].strip()
                
                if not length(key, 2, 20):
                    message = 'nada 3'

if not length(name, 2, 20):
        message = 'nada 1'
    elif not username(name):
        message = 'nada 2'
    
    list_label = [ int(x.split('_')[3]) for x in form if x.startswith('label_name_') ]
    
    if len(list_label) > 0:    
        len_label = max(list_label) + 1
        for i in range(len_label):
            
            i = str(i)
            if 'label_name_'+g.lan+'_'+i in form:
                key = form['label_name_'+g.lan+'_'+i].strip()
                
                if not length(key, 2, 20):
                    message = 'nada 3'
                elif not username(key):
                    message = 'nada 4'
    
                hash_map['value'][key] = {}

                for code in LIST_LANGUAGES:
                    if 'label_name_'+code+'_'+i in form:
                        value = form['label_'+code+'_'+i]
                        hash_map['value'][key][code] = value

                    else:
                        hash_map['value'][key][code] = ''

    if message is None:
        return (message, hash_map)

def set_token(auth_token):
    """
    Configure EvalAI Token.
    """
    """
    Invoked by `evalai set_token `.
    """
    if validators.length(auth_token, min=LEN_OF_TOKEN, max=LEN_OF_TOKEN):
        if not os.path.exists(AUTH_TOKEN_DIR):
            os.makedirs(AUTH_TOKEN_DIR)
        with open(AUTH_TOKEN_PATH, "w+") as fw:
            try:
                auth_token = {"token": "{}".format(auth_token)}  # noqa
                auth_token = json.dumps(auth_token)
                fw.write(auth_token)
            except (OSError, IOError) as e:
                echo(e)
            echo(
                style(
                    "Success: Authentication token is successfully set.",
                    bold=True,
                    fg="green",
                )
            )