Why is point_cloud2.py missing from sensor_msgs in ROS2?

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After subscribing to a PointCloud2 message in ROS2, I want to extract the PointCloud2 points from the message. In ROS1 I could do that with: sensor_msgs.point_cloud2.read_points(). However, point_cloud2 seems to be missing from sensor_msgs in ROS2. Here is the basic code I am trying to write:

import rclpy 
from rclpy.node import Node 
from sensor_msgs.msg import PointCloud2 
from sensor_msgs import point_cloud2

class my_node(Node):
    def __init__(self):
        super().__init__('my_node')    
        self.subscription = self.create_subscription(PointCloud2,'/points',self.lidar_callback,1)

    def lidar_callback(self, msg):
        pts = point_cloud2.read_points(msg, field_names=['x','y','z','intensity'])
        #Now process pts...

The 4th line fails, namely:

from sensor_msgs import point_cloud2

Any insights on how to do this in ROS2 Foxy?