Prefix one or multiple arguments with a Dockerfile command. The default is ``#``, for comments. Multiple args will
        be separated by a space.

        :param prefix: Dockerfile command to use, e.g. ``ENV`` or ``RUN``.
        :type prefix: unicode | str
        :param args: Arguments to be prefixed.

def prefix(self, prefix='#', *args):
        """
        Prefix one or multiple arguments with a Dockerfile command. The default is ``#``, for comments. Multiple args will
        be separated by a space.

        :param prefix: Dockerfile command to use, e.g. ``ENV`` or ``RUN``.
        :type prefix: unicode | str
        :param args: Arguments to be prefixed.
        """
        self.write(prefix)
        if args:
            self.write(' ')
            self.writeline(' '.join(map(six.text_type, args)))