How to use the @babel/helper-get-function-arity function in @babel/helper-get-function-arity

// need to add a wrapper since we can't change the references
      let build = buildPropertyMethodAssignmentWrapper;
      if (method.generator) {
        build = buildGeneratorPropertyMethodAssignmentWrapper;
      }
      const template = build({
        FUNCTION: method,
        FUNCTION_ID: id,
        FUNCTION_KEY: scope.generateUidIdentifier(id.name),
      }).expression;

      // shim in dummy params to retain function arity, if you try to read the
      // source then you'll get the original since it's proxied so it's all good
      const params = template.callee.body.body[0].params;
      for (let i = 0, len = getFunctionArity(method); i < len; i++) {
        params.push(scope.generateUidIdentifier("x"));
      }

      return template;
    }
  }

  method.id = id;
  scope.getProgramParent().references[id.name] = true;
}