diff --git a/uncompyle6/main.py b/uncompyle6/main.py
index fe4ae4ef..0b35d8c7 100644
--- a/uncompyle6/main.py
+++ b/uncompyle6/main.py
@@ -101,7 +101,9 @@ def decompile(
         )
     )
     if PYTHON_VERSION < 3.0 and bytecode_version >= 3.0:
-        write("# Warning: this version has problems handling the Python 3 byte type in contants properly.\n")
+        write(
+            "# Warning: this version has problems handling the Python 3 byte type in contants properly.\n"
+        )
 
     if co.co_filename:
         write("# Embedded file name: %s" % co.co_filename,)
diff --git a/uncompyle6/semantics/transform.py b/uncompyle6/semantics/transform.py
index 0069aa08..63b31a87 100644
--- a/uncompyle6/semantics/transform.py
+++ b/uncompyle6/semantics/transform.py
@@ -30,14 +30,18 @@ def is_docstring(node):
     except:
         return False
 
+
 def is_not_docstring(call_stmt_node):
     try:
-        return (call_stmt_node == "call_stmt" and
-                call_stmt_node[0][0] == "LOAD_STR" and
-                call_stmt_node[1] == "POP_TOP")
+        return (
+            call_stmt_node == "call_stmt"
+            and call_stmt_node[0][0] == "LOAD_STR"
+            and call_stmt_node[1] == "POP_TOP"
+        )
     except:
         return False
 
+
 class TreeTransform(GenericASTTraversal, object):
     def __init__(self, version, show_ast=None, is_pypy=False):
         self.version = version
@@ -133,7 +137,7 @@ class TreeTransform(GenericASTTraversal, object):
                 and 1 <= len(testtrue_or_false) <= 2
                 and raise_stmt.first_child().pattr == "AssertionError"
             ):
-                if  testtrue_or_false == "testtrue":
+                if testtrue_or_false == "testtrue":
                     # Skip over the testtrue because because it would
                     # produce a "not" and we don't want that here.
                     assert_expr = testtrue_or_false[0]
@@ -182,7 +186,7 @@ class TreeTransform(GenericASTTraversal, object):
                                 RAISE_VARARGS_1,
                             ],
                         )
-                        node.transformed_by="n_ifstmt"
+                        node.transformed_by = "n_ifstmt"
                         pass
                     pass
                 else:
@@ -264,9 +268,19 @@ class TreeTransform(GenericASTTraversal, object):
                     else_suite_index = 2
                 pass
             pass
-        elif len(n) > 1 and 1 == len(n[0]) and n[0] == "stmt" and n[1].kind == "stmt":
+        elif (
+            len(n) > 1
+            and isinstance(n[0], SyntaxTree)
+            and 1 == len(n[0])
+            and n[0] == "stmt"
+            and n[1].kind == "stmt"
+        ):
             else_suite_stmts = n[0]
-            if else_suite_stmts[0].kind not in ("ifstmt", "iflaststmt", "ifelsestmtl"):
+            if else_suite_stmts[0].kind not in (
+                "ifstmt",
+                "iflaststmt",
+                "ifelsestmtl",
+            ):
                 return node
             old_stmts = n
             n = else_suite_stmts[0]
@@ -327,14 +341,14 @@ class TreeTransform(GenericASTTraversal, object):
                 # import_from37 ::= LOAD_CONST LOAD_CONST IMPORT_NAME_ATTR importlist37 POP_TOP
                 # import_as37   ::= LOAD_CONST LOAD_CONST importlist37 store POP_TOP
                 # 'import_as37':     ( '%|import %c as %c\n', 2, -2),
-                node = SyntaxTree("import_as37",
-                                  [node[0], node[1], import_name_attr, store, node[-1]])
-                node.transformed_by="n_import_from37"
+                node = SyntaxTree(
+                    "import_as37", [node[0], node[1], import_name_attr, store, node[-1]]
+                )
+                node.transformed_by = "n_import_from37"
                 pass
             pass
         return node
 
-
     def n_list_for(self, list_for_node):
         expr = list_for_node[0]
         if expr == "expr" and expr[0] == "get_iter":
@@ -350,14 +364,18 @@ class TreeTransform(GenericASTTraversal, object):
             new_stmts = [node[0]]
             for i, sstmt in enumerate(node[1:]):
                 ann_assign = sstmt[0][0]
-                if (sstmt[0] == "stmt" and ann_assign == "ann_assign" and prev == "assign"):
+                if (
+                    sstmt[0] == "stmt"
+                    and ann_assign == "ann_assign"
+                    and prev == "assign"
+                ):
                     annotate_var = ann_assign[-2]
                     if annotate_var.attr == prev[-1][0].attr:
                         del new_stmts[-1]
                         sstmt[0][0] = SyntaxTree(
-                            "ann_assign_init",
-                            [ann_assign[0], prev[0], annotate_var])
-                        sstmt[0][0].transformed_by="n_stmts"
+                            "ann_assign_init", [ann_assign[0], prev[0], annotate_var]
+                        )
+                        sstmt[0][0].transformed_by = "n_stmts"
                         pass
                     pass
                 new_stmts.append(sstmt)
@@ -400,7 +418,7 @@ class TreeTransform(GenericASTTraversal, object):
                             )
                         ],
                     )
-                    docstring_ast.transformed_by="transform"
+                    docstring_ast.transformed_by = "transform"
                     del self.ast[i]
                     self.ast.insert(0, docstring_ast)
                     break