SMJobBlessUtil.py and python 3 on Apple Silicon

Try something like this (not a python expert so expecting comments):

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< #! /usr/bin/python 
---
> #! /usr/bin/python3
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<   except subprocess.CalledProcessError, e:
---
>   except subprocess.CalledProcessError as e:
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<     req = subprocess.check_output(args, stderr=open("/dev/null"))
<   except subprocess.CalledProcessError, e:
---
>     req = subprocess.check_output(args, stderr=open("/dev/null"), encoding="utf-8")
>   except subprocess.CalledProcessError as e:
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<     info = plistlib.readPlist(infoPath)
---
>     with open(infoPath, 'rb') as fp:
>       info = plistlib.load(fp)
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<     plistDump = subprocess.check_output(args)
<   except subprocess.CalledProcessError, e:
---
>     plistDump = subprocess.check_output(args, encoding="utf-8")
>   except subprocess.CalledProcessError as e:
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> 
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<     bytes = []
---
>     data = []
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<         bytes.append(int(hexStr, 16))
<     plist = plistlib.readPlistFromString(bytearray(bytes))
---
>         data.append(int(hexStr, 16))
> 
>     plist = plistlib.loads(bytes(data))
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<   if not info.has_key("SMPrivilegedExecutables"):
---
>   if "SMPrivilegedExecutables" not in info:
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<     if not info.has_key("CFBundleInfoDictionaryVersion") or info["CFBundleInfoDictionaryVersion"] != "6.0":
---
>     if "CFBundleInfoDictionaryVersion" not in info or info["CFBundleInfoDictionaryVersion"] != "6.0":
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<     if not info.has_key("CFBundleIdentifier") or info["CFBundleIdentifier"] != os.path.basename(toolPath):
---
>     if "CFBundleIdentifier" not in info or info["CFBundleIdentifier"] != os.path.basename(toolPath):
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<     if not info.has_key("SMAuthorizedClients"):
---
>     if "SMAuthorizedClients" not in info:
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<     if not launchd.has_key("Label") or launchd["Label"] != os.path.basename(toolPath):
---
>     if "Label" not in launchd or launchd["Label"] != os.path.basename(toolPath):
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<     if not toolInfo.has_key("CFBundleIdentifier"):
---
>     if "CFBundleIdentifier" not in toolInfo:
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<     if not isinstance(bundleID, basestring):
---
>     if not isinstance(bundleID, str):
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<   needsUpdate = not appInfo.has_key("SMPrivilegedExecutables")
---
>   needsUpdate = "SMPrivilegedExecutables" not in appInfo
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<     appToolDictSorted = sorted(appToolDict.iteritems(), key=operator.itemgetter(0))
<     oldAppToolDictSorted = sorted(oldAppToolDict.iteritems(), key=operator.itemgetter(0))
---
>     appToolDictSorted = sorted(appToolDict.items(), key=operator.itemgetter(0))
>     oldAppToolDictSorted = sorted(oldAppToolDict.items(), key=operator.itemgetter(0))
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<     plistlib.writePlist(appInfo, appInfoPlistPath)
<     print >> sys.stdout, "%s: updated" % appInfoPlistPath
---
>     with open(appInfoPlistPath, 'wb') as fp:
>       plistlib.dump(appInfo, fp)
>     print ("%s: updated" % appInfoPlistPath, file = sys.stdout)
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<     needsUpdate = not toolInfo.has_key("SMAuthorizedClients")
---
>     needsUpdate = "SMAuthorizedClients" not in toolInfo
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<       print >> sys.stdout, "%s: updated" % toolInfoPlistPath
---
>       print("%s: updated" % toolInfoPlistPath, file = sys.stdout)
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<   except CheckException, e:
---
>   except CheckException as e:
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<       print >> sys.stderr, "%s: %s" % (os.path.basename(sys.argv[0]), e.message)
---
>       print("%s: %s" % (os.path.basename(sys.argv[0]), e.message), file = sys.stderr)
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<       print >> sys.stderr, "%s: %s" % (path, e.message)
---
>       print("%s: %s" % (path, e.message), file = sys.stderr)
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<   except UsageException, e:
<     print >> sys.stderr, "usage: %s check /path/to/app" % os.path.basename(sys.argv[0])
<     print >> sys.stderr, "    %s setreq /path/to/app /path/to/app/Info.plist /path/to/tool/Info.plist..." % os.path.basename(sys.argv[0])
---
>   except UsageException as e:
>     print("usage: %s check /path/to/app" % os.path.basename(sys.argv[0]), file = sys.stderr)
>     print("    %s setreq /path/to/app /path/to/app/Info.plist /path/to/tool/Info.plist..." % os.path.basename(sys.argv[0]), file = sys.stderr)