[Python] Bad File Descriptor error in python writing to a pipe

I wrote a iTunes-replacement program to run in python, and it works well thanks to import pipes. Unfortunately, recently I receive the DeprecationWarning: 'pipes' is deprecated and slated for removal in Python 3.13

I decided to manually write to the pipe to talk to mpg123

mpgpipe = "/tmp/mpg123remote.cmd"
try:
os.mkfifo(mpgpipe)
print("Named pipe created successfully!")
except FileExistsError:
print("Named pipe already exists!")
except OSError as e:
print(f"Named pipe creation failed: {e}")
pipfd = os.open(mpgpipe, os.O_RDWR | os.O_NONBLOCK) # the file descriptor of the pipe


but in the body I get an OSError: [Errno 9] Bad file descriptor here's a runnable example:

#!/usr/bin/env python3

import os, io

mpgpipe = "/tmp/mpg123remote.cmd"
try:
os.mkfifo(mpgpipe)
print("Named pipe created successfully!")
except FileExistsError:
print("Named pipe already exists!")
except OSError as e:
print(f"Named pipe creation failed: {e}")
pipfd = os.open(mpgpipe, os.O_RDWR | os.O_NONBLOCK) # the file descriptor of the pipe

playlist=['a','b','c']
with io.FileIO(pipfd, 'wb') as f:
f.write("echo silence".encode())
currentlyplaying=1
with io.FileIO(pipfd, 'wb') as f:
s=f"echo load \"{playlist[currentlyplaying-1]}\""
f.write(s.encode())


what I cannot understand is that the error happens at the second call, immediately after the currentlyplaying=1 line

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