Honor the 'SOURCE_DATE_EPOCH' environment variable to allow for
determinitic builds.

--- a/Lib/py_compile.py
+++ b/Lib/py_compile.py
@@ -105,7 +105,10 @@ def compile(file, cfile=None, dfile=None, doraise=False):
     """
     with open(file, 'U') as f:
         try:
-            timestamp = long(os.fstat(f.fileno()).st_mtime)
+            if 'SOURCE_DATE_EPOCH' in os.environ:
+                timestamp = long(os.environ['SOURCE_DATE_EPOCH'])
+            else:
+                timestamp = long(os.fstat(f.fileno()).st_mtime)
         except AttributeError:
             timestamp = long(os.stat(file).st_mtime)
         codestring = f.read()
diff --git a/Python/import.c b/Python/import.c
index e47ce63..7eecf9c 100644
--- a/Python/import.c
+++ b/Python/import.c
@@ -945,6 +945,11 @@ write_compiled_module(PyCodeObject *co, char *cpathname, struct stat *srcstat, t
     /* Now write the true mtime (as a 32-bit field) */
     fseek(fp, 4L, 0);
     assert(mtime <= 0xFFFFFFFF);
+    if (Py_GETENV("SOURCE_DATE_EPOCH") != NULL) {
+	const char *epoch = Py_GETENV("SOURCE_DATE_EPOCH");
+	mtime = atoi(epoch);
+    }
+
     PyMarshal_WriteLongToFile((long)mtime, fp, Py_MARSHAL_VERSION);
     fflush(fp);
     fclose(fp);
/a><a href='/guix/tree/gnu/home/services/media.scm?id=d7bd22a4863214fd1df427bbebd1859eddd71f9b'>tree</a><a href='/guix/commit/gnu/home/services/media.scm?id=d7bd22a4863214fd1df427bbebd1859eddd71f9b'>commit</a><a href='/guix/diff/gnu/home/services/media.scm?id=d7bd22a4863214fd1df427bbebd1859eddd71f9b'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/gnu/home/services/media.scm'>
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<div class='path'>path: <a href='/guix/log/?id=d7bd22a4863214fd1df427bbebd1859eddd71f9b'>root</a>/<a href='/guix/log/gnu?id=d7bd22a4863214fd1df427bbebd1859eddd71f9b'>gnu</a>/<a href='/guix/log/gnu/home?id=d7bd22a4863214fd1df427bbebd1859eddd71f9b'>home</a>/<a href='/guix/log/gnu/home/services?id=d7bd22a4863214fd1df427bbebd1859eddd71f9b'>services</a>/<a href='/guix/log/gnu/home/services/media.scm?id=d7bd22a4863214fd1df427bbebd1859eddd71f9b'>media.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/gnu/home/services/media.scm?id=d7bd22a4863214fd1df427bbebd1859eddd71f9b&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2023-03-16 23:03:17 +0100'>2023-03-16</span></td><td><a href='/guix/commit/gnu/home/services/media.scm?id=8f219e658d8d2d89a2d6ec10729099130791a3a2'>home: services: kodi, znc, ssh-agent: Use 'match-record'.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/home/services/media.scm (home-kodi-services): Use 'match-record'
instead of 'match'.
* gnu/home/services/messaging.scm (home-znc-services): Likewise.
* gnu/home/services/ssh.scm (home-ssh-agent-services): Likewise.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2023-03-16 17:23:51 +0100'>2023-03-16</span></td><td><a href='/guix/commit/gnu/home/services/media.scm?id=6afd1fd6bccf3093c6e7b29ed816ee0d5a10c537'>home: services: kodi: Remove host-side use of (shepherd support).</a><span class='msg-avail'>...<span class='msg-tooltip'>This is a followup to 70056b1b2beebbc9f8ea2c34eacc57f379368ab3, which
inadvertently pulled in (shepherd support) on the host side.

* gnu/home/services/media.scm (home-kodi-services): Change 'command' and
'logfile' to gexps.  Add 'modules' field to 'shepherd-service'.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2023-03-16 14:33:16 +0100'>2023-03-16</span></td><td><a href='/guix/commit/gnu/home/services/media.scm?id=70056b1b2beebbc9f8ea2c34eacc57f379368ab3'>gnu: home: services: Add home-kodi-service-type.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/home/services/media.scm: New file.
* gnu/local.mk (GNU_SYSTEM_MODULES): Add it.
* po/guix/POTFILES.in: Likewise.
* doc/guix.texi (Media Home Services): Document it in new subsection.
</span></span></td><td>Jan (janneke) Nieuwenhuizen</td></tr>