hg: move unreachable code to where it could be reached

hg

@@ -1,59 +1,59 b''
 #!/usr/bin/env python3
 #
 # mercurial - scalable distributed SCM
 #
 # Copyright 2005-2007 Olivia Mackall <[e-mail]>
 #
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2 or any later version.
 
 import os
 import sys
 
 libdir = '@LIBDIR@'
 
 if libdir != '@' 'LIBDIR' '@':
     if not os.path.isabs(libdir):
         libdir = os.path.join(
             os.path.dirname(os.path.realpath(__file__)), libdir
         )
         libdir = os.path.abspath(libdir)
     sys.path.insert(0, libdir)
 
 # Make `pip install --user ...` packages available to the official Windows
 # build.  Most py2 packaging installs directly into the system python
 # environment, so no changes are necessary for other platforms.  The Windows
 # py2 package uses py2exe, which lacks a `site` module.  Hardcode it according
 # to the documentation.
 if getattr(sys, 'frozen', None) == 'console_exe':
     vi = sys.version_info
     appdata = os.environ.get('APPDATA')
     if appdata:
         sys.path.append(
             os.path.join(
                 appdata,
                 'Python',
                 'Python%d%d' % (vi[0], vi[1]),
                 'site-packages',
             )
         )
 
-from hgdemandimport import tracing
+try:
+    from hgdemandimport import tracing
+except ImportError:
+    sys.stderr.write(
+        "abort: couldn't find mercurial libraries in [%s]\n"
+        % ' '.join(sys.path)
+    )
+    sys.stderr.write("(check your install and PYTHONPATH)\n")
+    sys.exit(-1)
 
 with tracing.log('hg script'):
     # enable importing on demand to reduce startup time
-    try:
-        import hgdemandimport
+    import hgdemandimport
 
-        hgdemandimport.enable()
-    except ImportError:
-        sys.stderr.write(
-            "abort: couldn't find mercurial libraries in [%s]\n"
-            % ' '.join(sys.path)
-        )
-        sys.stderr.write("(check your install and PYTHONPATH)\n")
-        sys.exit(-1)
+    hgdemandimport.enable()
 
     from mercurial import dispatch
 
     dispatch.run()