Change in version.py

To deal with the case of previously installed version of msspec,
the order in which the version is checked has changed.
1- test if we can infer the version from the SCM
2- check if a VERSION file exists
3- take the version from the distribution

src/msspec/version.py

@@ -1,28 +1,31 @@
 # coding: utf-8
 # vim: set et sw=4 ts=4 sts=4 nu ai cc=+0 fdm=indent mouse=a:
 
+from setuptools_scm import get_version
 from pkg_resources import parse_version, DistributionNotFound, get_distribution
 from msspec.misc import LOGGER
 import os
 
+# find the version number
+# 1- Try to read it from the git info
+# 2- If it fails, try to read it from the VERSION file
+# 3- If it fails, try to read it from the distribution file
+
 try:
-    # try to find the version from egg info file
-    __version__ = get_distribution(__name__.strip('.version')).version
-except DistributionNotFound:
-    # otherwise try to get it from the SCM
-    try:
-        from setuptools_scm import get_version
     v = get_version(root='../../', relative_to=__file__, version_scheme="post-release")
     v = parse_version(v)
     if v._version.post[-1] == 0:
         __version__ = v.base_version
     else:
         __version__ = v.public
-    except (LookupError, ModuleNotFoundError):
-        # Ok, so there may be a VERSION file to look for it
+except (LookupError, ImportError):
     try:
         f = os.path.join(os.path.dirname(__file__), "../VERSION")
         with open(f, "r") as fd:
             __version__ = fd.read().strip('\n ')
     except:
+        try:
+            __version__ = get_distribution(__name__.strip('.version')).version
+        except DistributionNotFound:
             LOGGER.error("Unable to get the version number!")
+