Import ABC from collections.abc instead of collections for Python 3.9 compatibility.

Author: tirkarthi

odml/base.py

@@ -2,12 +2,15 @@
 """
 Collects common base functionality
 """
-import collections
 import posixpath
 
 from . import terminology
 from .tools.doc_inherit import allow_inherit_docstring
 
+try:
+    from collections.abc import Iterable
+except ImportError:
+    from collections import Iterable
 
 class BaseObject(object):
     _format = None
@@ -249,7 +252,7 @@ def append(self, section):
         if isinstance(section, BaseSection):
             self._sections.append(section)
             section._parent = self
-        elif isinstance(section, collections.Iterable) and not isinstance(section, str):
+        elif isinstance(section, Iterable) and not isinstance(section, str):
             raise ValueError("Use extend to add a list of Sections.")
         else:
             raise ValueError("Can only append objects of type Section.")
@@ -261,7 +264,7 @@ def extend(self, sec_list):
         :param sec_list: Iterable containing odML Section entries.
         """
         from odml.section import BaseSection
-        if not isinstance(sec_list, collections.Iterable):
+        if not isinstance(sec_list, Iterable):
             raise TypeError("'%s' object is not iterable" % type(sec_list).__name__)
 
         # Make sure only Sections with unique names will be added.

odml/section.py

@@ -1,5 +1,4 @@
 # -*- coding: utf-8
-import collections
 import uuid
 
 from . import base
@@ -11,6 +10,10 @@
 # it MUST however not be used to create any Property objects
 from .tools.doc_inherit import inherit_docstring, allow_inherit_docstring
 
+try:
+    from collections.abc import Iterable
+except ImportError:
+    from collections import Iterable
 
 @allow_inherit_docstring
 class BaseSection(base.Sectionable):
@@ -322,7 +325,7 @@ def append(self, obj):
         elif isinstance(obj, BaseProperty):
             self._props.append(obj)
             obj._parent = self
-        elif isinstance(obj, collections.Iterable) and not isinstance(obj, str):
+        elif isinstance(obj, Iterable) and not isinstance(obj, str):
             raise ValueError("odml.Section.append: "
                              "Use extend to add a list of Sections or Properties.")
         else:
@@ -336,7 +339,7 @@ def extend(self, obj_list):
 
         :param obj_list: Iterable containing Section and Property entries.
         """
-        if not isinstance(obj_list, collections.Iterable):
+        if not isinstance(obj_list, Iterable):
             raise TypeError("'%s' object is not iterable" % type(obj_list).__name__)
 
         # Make sure only Sections and Properties with unique names will be added.