<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def visit_rule(self, node, rule):
 """Assign a name to the Expression and return it."""

        label, equals, expression = rule
        expression.name = label  # Assign a name to the expr.
        return expression