<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def on_for(self, node):
 # ('target', 'iter', 'body', 'orelse') """For blocks."""

        for val in self.run(node.iter):
            self.node_assign(node.target, val)
            self._interrupt = None
            for tnode in node.body:
                self.run(tnode)
                if self._interrupt is not None:
                    break
            if isinstance(self._interrupt, ast.Break):
                break
        else:
            for tnode in node.orelse:
                self.run(tnode)
        self._interrupt = None