Getting my head around os.pipe in python

pipe.py

import os

read, write = os.pipe()

# Variable 'parent' is the process id of the parent fork
# It gets a value of 0 when the parent process exits
parent = os.fork()

if parent:

    # If write isn't closed, then when the child process
    # never exits
    os.close(write)

    print("Parent reading")
    read = os.fdopen(read)
    print("Text = ", read.read())

    exit()

else:

    os.close(read)

    print("Child writing")
    write = os.fdopen(write, "w")
    write.write("Written by child")

    print("Child closing")
    write.close()

    exit()