sagemathgh-38521: Fix `sage_bootstrap.flock` for Python 3.13 (fedora-41)
    
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Seen on Fedora 41, which already ships Python 3.13:

https://github.com/mkoeppe/sage/actions/runs/10426436105/job/28893965205
#step:11:10930
```
#28 943.2   [pip-24.0]   [spkg-pipinst]   File
"/sage/build/bin/../sage_bootstrap/flock.py", line 15, in <module>
#28 943.2   [pip-24.0]   [spkg-pipinst]     import pipes
#28 943.2   [pip-24.0]   [spkg-pipinst] ModuleNotFoundError: No module
named 'pipes'
```

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URL: sagemath#38521
Reported by: Matthias Köppe
Reviewer(s): François Bissey, Kwankyu Lee, Matthias Köppe

build/sage_bootstrap/compat/__init__.py

@@ -28,3 +28,11 @@
     from StringIO import StringIO
 except ImportError:
     from io import StringIO
+
+
+try:
+    # Use this for Python 3.  This function is available for Python >= 3.3
+    from shlex import quote
+except ImportError:
+    # Use this for Python 2.  This function is available for Python < 3.13
+    from pipes import quote

build/sage_bootstrap/flock.py

@@ -12,10 +12,11 @@
 
 import fcntl
 import os
-import pipes
 import sys
 import argparse
 
+from sage_bootstrap.compat import quote
+
 
 class FileType(argparse.FileType):
     """
@@ -105,7 +106,7 @@ def run(argv=None):
             kind = "exclusive"
 
         sys.stderr.write("Waiting for {0} lock to run {1} ... ".format(
-            kind, ' '.join(pipes.quote(arg) for arg in command)))
+            kind, ' '.join(quote(arg) for arg in command)))
         fcntl.flock(lock, locktype)
         sys.stderr.write("ok\n")