def METHOD_NAME(self, var: str, *values):
    """
    This function adds a VALUES clause to the WHERE query.
    Note only one VALUES clause can be added.
    Arguments:
        var - variable for filtering
        *values - a variable number of values to be added for filtering \
            if values are classes, please input as "prefix:class"
    """
    if "VALUES" in self.where_string:
        logger.warning("VALUES clause has already been defined!")
        raise QueryBuilderError("VALUES clause has already been defined!")
    # Add start of VALUES clause inside the WHERE clause
    self.where_string += "VALUES ?" + var + self.whitespace + "{"
    # Add each value to the string
    for value in values:
        # If value is a string and is not in prefix:iri format
        if isinstance(value, str) and ":" not in value:
            self.where_string += "'" + (value) + "'" + self.whitespace
        else:
            self.where_string += str(value) + self.whitespace
    # Close the VALUES clause
    self.where_string += "} \n"
    return self