Add any predefined or custom extension.

        Args:
            extension: Extension to add to the processor.

        Returns:
            The DictMentor itself for chaining.

def bind(self, extension: Extension) -> 'DictMentor':
        """
        Add any predefined or custom extension.

        Args:
            extension: Extension to add to the processor.

        Returns:
            The DictMentor itself for chaining.
        """
        if not Extension.is_valid_extension(extension):
            raise ValueError("Cannot bind extension due to missing interface requirements")
        self._extensions.append(extension)

        return self