use datetime module to convert string date to numeric date

python/lammps/__init__.py

@@ -15,7 +15,7 @@ from .pylammps import *
 
 # convert module string version to numeric version
 def get_version_number():
-    import re
+    from datetime import datetime
     from sys import version_info
     vstring = None
     if version_info.major == 3 and version_info.minor >= 8:
@@ -32,18 +32,7 @@ def get_version_number():
     if not vstring:
         return 0
 
-    vregex = re.compile(r"([0-9]+)([A-Za-z]+)(2[0-9]+)")
-    m = vregex.match(vstring)
-
-    if (m):
-        month2num = { 'Jan' : 1, 'Feb' : 2, 'Mar' : 3, 'Apr' : 4, 'May' : 5, 'Jun' : 6,
-                'Jul' : 7, 'Aug' : 8, 'Sep' : 9, 'Oct' : 10, 'Nov' : 11, 'Dec' : 12 }
-        try:
-            vernum = int(m.group(3))*10000
-            vernum += month2num[m.group(2)]*100
-            vernum += int(m.group(1))
-        except:
-            exit('Failure to parse version string: %s' % verstr)
-    return vernum
+    d = datetime.strptime(vstring, "%d%b%Y")
+    return d.year*10000 + d.month*100 + d.day
 
 __version__ = get_version_number()