StreamPlayer not working anymore

[Skelbti]

music21 version

9.9.1

Operating System(s) checked
macOS Sequoia 15.7.1 (Apple Silicon, M2)

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Problem summary
music21.midi.realtime.StreamPlayer fails on macOS ARM (Apple Silicon) with Python 3.14, even when pygame is correctly installed.
It raises StreamPlayerException('StreamPlayer requires pygame. Install first') although import pygame works fine.

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Steps to reproduce

from music21 import *

b = corpus.parse('bwv66.6')
sp = midi.realtime.StreamPlayer(b)
sp.play()

Full traceback

Traceback (most recent call last):
  File "test.py", line 5, in <module>
    sp = midi.realtime.StreamPlayer(b)
  File "/music21/midi/realtime.py", line 94, in __init__
    raise StreamPlayerException('StreamPlayer requires pygame.  Install first')
music21.midi.realtime.StreamPlayerException: StreamPlayer requires pygame.  Install first

Expected vs. actual behavior

Expected: StreamPlayer should detect pygame and allow real-time playback.
Actual: Raises an exception claiming pygame is missing even though it’s installed.

More information

• Python version: 3.14.0 (via Homebrew but it's the same with normal installer)
• music21 version: 9.9.1
• pygame version: 2.6.1 (pip show pygame confirms installation)
• Architecture: ARM64 (Apple Silicon)

[mscuthbert]

Thanks -- apparently we were still using a pre-1.9 exception code. PR #1836 fixes it -- appreciate it.