def METHOD_NAME(self):
    """This method allows transforms to be assigned directly to shader
    template variables. 
    Example::
        code = 'void main() { gl_Position = $transform($position); }'
        func = shaders.Function(code)
        tr = STTransform()
        func['transform'] = tr  # use tr's forward mapping for $function
    """
    return self.shader_map()