def __init__(self, node, parameter_name, center=(0, 0)):
        """Store arguments.

        Parameters
        ==========
        node (graphman.calnode.main.CallableNode object)
            node to which this socket belongs.
        parameter_name (string)
            represents the name of the parameter.
        """
        ### store arguments

        ## node instance
        self.node = node

        ## store parameter name argument
        self.parameter_name = parameter_name

        ### assign image and create rect from it

        self.image = HOLLOW_SOCKET_CIRCLE_SURF
        self.rect = self.image.get_rect()

        ### position rect
        setattr(self.rect, "center", center)
Store arguments.

        Parameters
        ==========
        node (graphman.calnode.main.CallableNode object)
            node to which this socket belongs.
        parameter_name (string)
            represents the name of the parameter.
        
nodezator/graphman/socket/placeholder.py