diff --git a/test/Makefile b/test/Makefile
index 04546f64..0869dae5 100644
--- a/test/Makefile
+++ b/test/Makefile
@@ -268,6 +268,7 @@ check-bytecode-3.6:
 
 #: Check deparsing Python 3.7
 check-bytecode-3.7:
+	$(PYTHON) test_pythonlib.py --bytecode-3.7-run --verify-run
 	$(PYTHON) test_pythonlib.py --bytecode-3.7 --weak-verify
 
 #: Check deparsing Python 3.8
diff --git a/test/bytecode_3.7_run/01_and_not_else.pyc b/test/bytecode_3.7_run/01_and_not_else.pyc
new file mode 100644
index 00000000..797183f5
Binary files /dev/null and b/test/bytecode_3.7_run/01_and_not_else.pyc differ
diff --git a/test/simple_source/bug37/01_and_not_else.py b/test/simple_source/bug37/01_and_not_else.py
new file mode 100644
index 00000000..3a51716a
--- /dev/null
+++ b/test/simple_source/bug37/01_and_not_else.py
@@ -0,0 +1,16 @@
+# From 3.7.3 base64.py
+# Bug was handling "and not" in an
+# if/else in the presence of better Python bytecode generatation
+
+# RUNNABLE!
+def foo(foldnuls, word):
+    x = 5 if foldnuls and not word else 6
+    return x
+
+for expect, foldnuls, word in (
+        (6, True, True),
+        (5, True, False),
+        (6, False, True),
+        (6, False, False)
+        ):
+   assert foo(foldnuls, word) == expect
diff --git a/uncompyle6/parsers/parse37.py b/uncompyle6/parsers/parse37.py
index 7185a117..dc2a63d8 100644
--- a/uncompyle6/parsers/parse37.py
+++ b/uncompyle6/parsers/parse37.py
@@ -111,6 +111,12 @@ class Python37Parser(Python36Parser):
         ifelsestmt                 ::= testexpr c_stmts_opt jf_cfs else_suite opt_come_from_except
 
         _ifstmts_jump              ::= c_stmts_opt come_froms
+
+        and_not                    ::= expr jmp_false expr POP_JUMP_IF_TRUE
+
+        expr                       ::= conditional37
+        conditional37              ::= and_not expr JUMP_FORWARD COME_FROM expr COME_FROM
+
         """
 
     def customize_grammar_rules(self, tokens, customize):
diff --git a/uncompyle6/semantics/customize37.py b/uncompyle6/semantics/customize37.py
index d756920c..e0c67ced 100644
--- a/uncompyle6/semantics/customize37.py
+++ b/uncompyle6/semantics/customize37.py
@@ -24,6 +24,8 @@ def customize_for_version37(self, version):
 
     PRECEDENCE['attribute37'] = 2
     TABLE_DIRECT.update({
+        'and_not':  ( '%c and not %c',
+                      (0, 'expr'), (2, 'expr') ),
         'async_forelse_stmt':  (
             '%|async for %c in %c:\n%+%c%-%|else:\n%+%c%-\n\n',
             (7, 'store'), (1, 'expr'), (17, 'for_block'), (25, 'else_suite') ),
@@ -54,5 +56,6 @@ def customize_for_version37(self, version):
             (0, 19 ) ),
         'compare_chained2c_37': (
             '%[3]{pattr.replace("-", " ")} %p %p', (0, 19), (6, 19) ),
+        'conditional37': ( '%p if %p else %p', (1, 'expr', 27), (0, 27), (4, 'expr', 27) ),
 
         })