diff --git a/decompyle3/semantics/consts.py b/decompyle3/semantics/consts.py
index 301fb664..06b5d26f 100644
--- a/decompyle3/semantics/consts.py
+++ b/decompyle3/semantics/consts.py
@@ -592,9 +592,12 @@
     "store": MAP_R,
 }
 
-ASSIGN_TUPLE_PARAM = lambda param_name: SyntaxTree(  # noqa
-    "expr", [Token("LOAD_FAST", pattr=param_name)]
-)
+
+def assign_tuple_parameter_tree(param_name) -> SyntaxTree:
+    return SyntaxTree("expr", [Token("LOAD_FAST", pattr=param_name)])
+
+
+ASSIGN_TUPLE_PARAM = assign_tuple_parameter_tree
 
 escape = re.compile(
     r"""
diff --git a/decompyle3/semantics/customize37.py b/decompyle3/semantics/customize37.py
index 655382c1..86effce5 100644
--- a/decompyle3/semantics/customize37.py
+++ b/decompyle3/semantics/customize37.py
@@ -24,6 +24,7 @@
 from decompyle3.scanners.tok import Token
 from decompyle3.semantics.consts import (
     INDENT_PER_LEVEL,
+    NO_PARENTHESIS_EVER,
     PRECEDENCE,
     TABLE_DIRECT,
     TABLE_R,
@@ -41,6 +42,7 @@ def escape_format(s):
 
 FSTRING_CONVERSION_MAP = {1: "!s", 2: "!r", 3: "!a", "X": ":X"}
 
+
 #######################
 def customize_for_version37(self, version):
     ########################
@@ -162,7 +164,7 @@ def customize_for_version37(self, version):
             "await_expr": ("await %p", (0, PRECEDENCE["await_expr"] - 1)),
             "await_stmt": ("%|%c\n", 0),
             "c_async_with_stmt": ("%|async with %c:\n%+%c%-", (0, "expr"), 3),
-            "call_ex": ("%c(%p)", (0, "expr"), (1, 100)),
+            "call_ex": ("%c(%p)", (0, "expr"), (1, NO_PARENTHESIS_EVER)),
             "compare_chained_middlea_37": (
                 "%p %p",
                 (0, PRECEDENCE["compare"] - 1),
@@ -419,7 +421,7 @@ def customize_for_version37(self, version):
 
     TABLE_R.update(
         {
-            "CALL_FUNCTION_EX": ("%c(*%P)", 0, (1, 2, ", ", 100)),
+            "CALL_FUNCTION_EX": ("%c(*%P)", 0, (1, 2, ", ", NO_PARENTHESIS_EVER)),
             # Not quite right
             "CALL_FUNCTION_EX_KW": ("%c(**%C)", 0, (2, 3, ",")),
         }
@@ -465,7 +467,7 @@ def call36_dict(node):
         We will source-code use line breaks to guide us when to break.
         """
         p = self.prec
-        self.prec = 100
+        self.prec = NO_PARENTHESIS_EVER
 
         self.indent_more(INDENT_PER_LEVEL)
         sep = INDENT_PER_LEVEL[:-1]
@@ -770,7 +772,7 @@ def n_call(node):
             if args_node in ("pos_arg", "expr"):
                 args_node = args_node[0]
             if args_node == "build_list_unpack":
-                template = ("*%P)", (0, len(args_node) - 1, ", *", 100))
+                template = ("*%P)", (0, len(args_node) - 1, ", *", NO_PARENTHESIS_EVER))
                 self.template_engine(template, args_node)
             else:
                 if len(node) - nargs > 3:
@@ -789,10 +791,19 @@ def n_call(node):
             and opname == "CALL_FUNCTION_1"
             or not re.match(r"\d", opname[-1])
         ):
-            template = "(%c)(%p)" if node[0][0] == "lambda_body" else "%c(%p)"
-            self.template_engine(
-                (template, (0, "expr"), (1, PRECEDENCE["yield"] - 1)), node
-            )
+            if node[0][0] == "lambda_body":
+                self.template_engine(
+                    (
+                        "(\n%+%|%c%-\n)(%p)",
+                        (0, ("expr", "arg")),
+                        (1, PRECEDENCE["yield"] - 1),
+                    ),
+                    node,
+                )
+            else:
+                self.template_engine(
+                    ("%c(%p)", (0, ("expr", "arg")), (1, NO_PARENTHESIS_EVER)), node
+                )
             self.prec = p
             self.prune()
         else:
@@ -1190,7 +1201,7 @@ def n_call_ex_kw(node):
         if value == "":
             fmt = "%c(%p)"
         else:
-            fmt = "%c" + ("(%s, " % value).replace('%', '%%') + "%p)"
+            fmt = "%c" + ("(%s, " % value).replace("%", "%%") + "%p)"
 
         self.template_engine(
             (fmt, (0, "expr"), (2, "build_map_unpack_with_call", 100)), node
@@ -1209,7 +1220,7 @@ def n_call_ex_kw2(node):
         if value == "":
             fmt = "%c(%p)"
         else:
-            fmt = "%c" + ("(%s, " % value).replace('%', '%%') + "%p)"
+            fmt = "%c" + ("(%s, " % value).replace("%", "%%") + "%p)"
 
         self.template_engine(
             (fmt, (0, "expr"), (2, "build_map_unpack_with_call", 100)), node
diff --git a/decompyle3/semantics/customize38.py b/decompyle3/semantics/customize38.py
index 2022832f..0893a643 100644
--- a/decompyle3/semantics/customize38.py
+++ b/decompyle3/semantics/customize38.py
@@ -19,7 +19,7 @@
 # Python 3.8+ changes
 #######################
 
-from decompyle3.semantics.consts import PRECEDENCE, TABLE_DIRECT
+from decompyle3.semantics.consts import NO_PARENTHESIS_EVER, PRECEDENCE, TABLE_DIRECT
 from decompyle3.semantics.customize37 import FSTRING_CONVERSION_MAP
 from decompyle3.semantics.helper import escape_string, strip_quotes
 
@@ -380,7 +380,7 @@ def n_set_afor(node):
 
     def n_formatted_value_debug(node):
         p = self.prec
-        self.prec = 100
+        self.prec = NO_PARENTHESIS_EVER
 
         formatted_value = node[1]
         value_equal = node[0].attr
diff --git a/test/bytecode_3.7/code-fragment/generator/03_generator_compendium.pyc b/test/bytecode_3.7/code-fragment/generator/03_generator_compendium.pyc
new file mode 100644
index 00000000..79fb29ec
Binary files /dev/null and b/test/bytecode_3.7/code-fragment/generator/03_generator_compendium.pyc differ
diff --git a/test/simple_source/generator_start/03_generator_compendium.py b/test/simple_source/generator_start/03_generator_compendium.py
new file mode 100644
index 00000000..0b1f8e9f
--- /dev/null
+++ b/test/simple_source/generator_start/03_generator_compendium.py
@@ -0,0 +1,84 @@
+# These are adapted from generators found when byte compiling the
+# entire set of 3.8 installed packages on my disk.
+# Many examples come from packages like sympy or numpy
+
+# fmt: off
+# generator bugs
+(i
+ for i
+ in
+ range(10)
+ )
+
+tuple(j
+       for j
+       in t
+       if i != j)
+
+# # 3.8.12 weakrefset.py
+# (e
+#  for s
+#  in ("a", "b")
+#  for e
+#  in s)
+
+# # Python 3.8.2 line 683 of git/refs/symbolic.py
+# # Bug was in handling "or not"
+# (r
+#  for r
+#  in (0, 1, 2, 3)
+#  if r
+#  or
+#  not
+#  5 % 2)
+
+# # line 1512 of sympy/core/mul.py
+# # Bug was handling "and"
+# (x
+#   and
+#   (x + 1 % 2)
+#  is True for
+#  x
+#  in (0, 1, 2)
+#  )
+
+# # line 330 of 3.8.12 setuptools/config.py
+# # Problem was in handling or True
+# (
+#  path
+#  for path in __file__
+#  if (path or True))
+
+# # Line 602 of 3.8.2 nltk/corpus/reader/framenet.py
+# # Bug was handling looping jump of chained comparison inside comp_if.
+# (1
+#  for x,
+#  y
+#  in __file__
+#  if 2 <= y
+#  < 3
+#  or 5
+#  <= x
+#  < 6)
+
+# # The problem was handing IfExp as part of a tuple, i.e.
+# #  (None if .. and .. else)
+# (
+#  (k,
+#   (None if
+#    k
+#    and v
+#    else v)
+#    )
+#  for k, v in
+#  {"foo": "bar"}
+#  )
+
+# # line 1086 of 3.8.12 test/test_asyncgen.py
+# # Bug was hooking genexpr_func_async to return_expr_lambda in grammar
+# # and writing a semantic action for this when the code is decompiled
+# # independant of the calling context.
+# (i * 2
+#  async
+#  for i
+#  in range(10))