From a0909405807e377769597cf1376c7b51dec45f25 Mon Sep 17 00:00:00 2001
From: Dekara VanHoc <50260825+dekaravanhoc@users.noreply.github.com>
Date: Fri, 21 Jan 2022 16:37:29 +0100
Subject: [PATCH] Update to collections.abc

Update to new abstract class for instance check of collections
Added Fallback for oder Python Versions
---
 backtrader/writer.py | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/backtrader/writer.py b/backtrader/writer.py
index 1f765d464..d69a2ec6d 100644
--- a/backtrader/writer.py
+++ b/backtrader/writer.py
@@ -26,6 +26,11 @@
 import itertools
 import sys
 
+try:
+    collectionsAbc = collections.abc
+except AttributeError:
+    collectionsAbc = collections
+
 import backtrader as bt
 from backtrader.utils.py3 import (map, with_metaclass, string_types,
                                   integer_types)
@@ -205,7 +210,7 @@ def writedict(self, dct, level=0, recurse=False):
                     self.writelineseparator(level=level)
                 self.writeline(kline)
                 self.writedict(val, level=level + 1, recurse=True)
-            elif isinstance(val, (list, tuple, collections.Iterable)):
+            elif isinstance(val, (list, tuple, collectionsAbc.Iterable)):
                 line = ', '.join(map(str, val))
                 self.writeline(kline + ' ' + line)
             else: