Migrate to pyproject.toml build

cps/constants.py

@@ -19,9 +19,6 @@
 import sys
 import os
 from collections import namedtuple
-from sqlalchemy import __version__ as sql_version
-
-sqlalchemy_version2 = ([int(x) for x in sql_version.split('.')] >= [2, 0, 0])
 
 # APP_MODE - production, development, or test
 APP_MODE             = os.environ.get('APP_MODE', 'production')
@@ -176,6 +173,7 @@ BookMeta = namedtuple('BookMeta', 'file_path, extension, title, author, cover, d
 
 # python build process likes to have x.y.zbw -> b for beta and w a counting number
 STABLE_VERSION = {'version': '0.6.24b'}
+_version = STABLE_VERSION['version']
 
 NIGHTLY_VERSION = dict()
 NIGHTLY_VERSION[0] = '$Format:%H$'