Add Python3.8 support, fix import

Uses try/catch to still support 2.7 too

.travis.yml

@@ -8,6 +8,7 @@ python:
   - "3.5"
   - "3.6"
   - "3.7"
+  - "3.8"
 install:
   - pip install -U pip setuptools
   - pip install tox-travis pre-commit

setup.py

@@ -46,6 +46,7 @@ setup(
         'Programming Language :: Python :: 3.5',
         'Programming Language :: Python :: 3.6',
         'Programming Language :: Python :: 3.7',
+        'Programming Language :: Python :: 3.8',
     ],
     keywords='stix stix2 json cti cyber threat intelligence',
     packages=find_packages(exclude=['*.test', '*.test.*']),

stix2/base.py

@@ -1,6 +1,5 @@
 """Base classes for type definitions in the STIX2 library."""
 
-import collections
 import copy
 import datetime as dt
 import uuid
@@ -20,6 +19,12 @@ from .utils import NOW, find_property_index, format_datetime, get_timestamp
 from .utils import new_version as _new_version
 from .utils import revoke as _revoke
 
+try:
+    from collections.abc import Mapping
+except ImportError:
+    from collections import Mapping
+
+
 __all__ = ['STIXJSONEncoder', '_STIXBase']
 
 DEFAULT_ERROR = "{type} must have {property}='{expected}'."
@@ -68,7 +73,7 @@ def get_required_properties(properties):
     return (k for k, v in properties.items() if v.required)
 
 
-class _STIXBase(collections.Mapping):
+class _STIXBase(Mapping):
     """Base class for STIX object types"""
 
     def object_properties(self):

stix2/properties.py

@@ -2,7 +2,6 @@
 
 import base64
 import binascii
-import collections
 import copy
 import inspect
 import re
@@ -20,6 +19,11 @@ from .exceptions import (
 )
 from .utils import _get_dict, get_class_hierarchy_names, parse_into_datetime
 
+try:
+    from collections.abc import Mapping
+except ImportError:
+    from collections import Mapping
+
 ERROR_INVALID_ID = (
     "not a valid STIX identifier, must match <object-type>--<UUID>: {}"
 )
@@ -198,7 +202,7 @@ class ListProperty(Property):
             else:
                 obj_type = self.contained
 
-            if isinstance(valid, collections.Mapping):
+            if isinstance(valid, Mapping):
                 try:
                     valid._allow_custom
                 except AttributeError:

tox.ini

@@ -1,5 +1,5 @@
 [tox]
-envlist = py27,py34,py35,py36,py37,style,isort-check,packaging
+envlist = py27,py34,py35,py36,py37,py38,style,isort-check,packaging
 
 [testenv]
 deps =
@@ -11,6 +11,7 @@ deps =
   taxii2-client
   fuzzywuzzy
   haversine
+  python-Levenshtein
   medallion
 commands =
   python -m pytest --cov=stix2 stix2/test/ --cov-report term-missing -W ignore::stix2.exceptions.STIXDeprecationWarning
@@ -42,7 +43,8 @@ commands =
 [travis]
 python =
   2.7: py27, style
-  3.4: py34, style
-  3.5: py35, style
-  3.6: py36, style, packaging
-  3.7: py37, style
+  3.4: py34
+  3.5: py35
+  3.6: py36
+  3.7: py37
+  3.7: py38, style, packaging