add __version__ to the botstory module

botstory/__init__.py

@@ -1,5 +1,9 @@
 from .ast.callable import EndOfStory
 from .ast.forking import SwitchOnValue, Undefined
 from .story import Story
+import os
 
 __all__ = [EndOfStory, Story, SwitchOnValue]
+
+with open(os.path.join(os.path.dirname(os.path.realpath(__file__)), '..', 'version.txt')) as version_file:
+    __version__ = version_file.read().strip()

botstory/story_test.py

@@ -3,14 +3,21 @@
 import pytest
 from unittest.mock import call
 
+import botstory
 from . import di
 from .integrations import mockdb, mockhttp
 from .middlewares import location, text
 from .utils import answer, SimpleTrigger
+import os
 
 logger = logging.getLogger(__name__)
 
 
+def test_botstory_has_current_version_of_module():
+    with open(os.path.join(os.path.dirname(os.path.realpath(__file__)), '..', 'version.txt')) as version_file:
+        assert botstory.__version__ == version_file.read().strip()
+
+
 @pytest.mark.asyncio
 async def test_should_run_sequence_of_parts():
     trigger_1 = SimpleTrigger()