Fix import errors on Python version >= 3.10

vector/base.py

@@ -1,6 +1,10 @@
 import operator
 from contextlib import contextmanager
-from collections import Iterable
+try:
+    # since python 3.10
+    from collections.abc import Iterable
+except ImportError:
+    from collections import Iterable
 
 class View:
     def draw(self, object, offset=None, **kw):

vector/svg.py

@@ -2,7 +2,11 @@
 from contextlib import contextmanager
 from . import base
 from math import sin, cos, radians
-from collections import Iterable
+try:
+    # since python 3.10
+    from collections.abc import Iterable
+except ImportError:
+    from collections import Iterable
 from urllib.parse import urlunparse, ParseResult
 import operator
 from textwrap import TextWrapper