Python 3.10 compatibility (#97)

Author: sbelluzzo

.github/workflows/ci.yml

@@ -12,7 +12,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: [ 3.6, 3.7, 3.8 ]
+        python-version: [ 3.7, 3.8, 3.9, '3.10' ]
 
     steps:
       - name: Checkout repository

setup.py

@@ -25,7 +25,7 @@
       ],
       extras_require={
           "test": [
-              'pytest==6.2.1',
+              'pytest==6.2.5',
               'pylint==2.6.0',
               'pytest-cov==2.10.1',
           ]

target_postgres/db_sync.py

@@ -2,12 +2,12 @@
 import sys
 import psycopg2
 import psycopg2.extras
-import collections
 import inflection
 import re
 import uuid
 import itertools
 import time
+from collections.abc import MutableMapping
 from singer import get_logger
 
 
@@ -147,7 +147,7 @@ def flatten_record(d, flatten_schema=None, parent_key=[], sep='__', level=0, max
     items = []
     for k, v in d.items():
         new_key = flatten_key(k, parent_key, sep)
-        if isinstance(v, collections.MutableMapping) and level < max_level:
+        if isinstance(v, MutableMapping) and level < max_level:
             items.extend(flatten_record(v, flatten_schema, parent_key + [k], sep=sep, level=level + 1,
                                         max_level=max_level).items())
         else: