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[kallisti5]

I was able to get trac running under PyPy in ​https://foss.heptapod.net/pypy/pypy/-/issues/3528

Originally it was crashing on ticket queries, but switching psycopg2 to psycopg2cffi via this patch below resolved the crashing:

diff --git a/trac/db/postgres_backend.py b/trac/db/postgres_backend.py
index f9f910630..8670f83ac 100644
--- a/trac/db/postgres_backend.py
+++ b/trac/db/postgres_backend.py
@@ -31,6 +31,14 @@ from trac.util.html import Markup
 from trac.util.text import empty, exception_to_unicode, to_unicode
 from trac.util.translation import _
 
+# Attempt to use psycopg2cffi in compatibility mode if available
+# this enables usage of psycopg2cffi under pypy
+try:
+    from psycopg2cffi import compat
+    compat.register()
+except ImportError:
+    pass
+
 try:
     import psycopg2 as psycopg
     import psycopg2.extensions