ENH: dynamic versioning

.gitignore

@@ -9,3 +9,5 @@
 env
 build
 dist
+
+dtool/version.py

dtool/__init__.py

@@ -1,3 +1,26 @@
 """dtool package."""
 
-__version__ = "3.26.2"
+import logging
+
+logger = logging.getLogger(__name__)
+
+# workaround for diverging python versions:
+try:
+    from importlib.metadata import version, PackageNotFoundError
+    logger.debug("imported version, PackageNotFoundError from importlib.metadata")
+except ModuleNotFoundError:
+    from importlib_metadata import version, PackageNotFoundError
+    logger.debug("imported version, PackageNotFoundError from importlib_metadata")
+
+# first, try to determine dynamic version at runtime
+try:
+    __version__ = version(__name__)
+    logger.debug("Determined version %s via importlib_metadata.version", __version__)
+except PackageNotFoundError:
+    # if that fails, check for static version file written by setuptools_scm
+    try:
+        from .version import version as __version__
+        logger.debug("Determined version %s from autogenerated dtool/version.py", __version__)
+    except Exception as e:
+        logger.debug("All efforts to determine version failed: %s", e)
+        __version__ = None