[cleanup,build] Cleanup some build-related code

Fixes an issue in 7ab56be2c7

setup.py

@@ -11,18 +11,28 @@ except ImportError:
     setuptools_available = False
 from distutils.spawn import spawn
 
-# Get the version from yt_dlp/version.py without importing the package
-exec(compile(open('yt_dlp/version.py').read(), 'yt_dlp/version.py', 'exec'))
 
+def read(fname):
+    with open(fname, encoding='utf-8') as f:
+        return f.read()
+
+
+# Get the version from yt_dlp/version.py without importing the package
+def read_version(fname):
+    exec(compile(read(fname), fname, 'exec'))
+    return locals()['__version__']
+
+
+VERSION = read_version('yt_dlp/version.py')
 
 DESCRIPTION = 'A youtube-dl fork with additional features and patches'
 
 LONG_DESCRIPTION = '\n\n'.join((
     'Official repository: <https://github.com/yt-dlp/yt-dlp>',
     '**PS**: Some links in this document will not work since this is a copy of the README.md from Github',
-    open('README.md', encoding='utf-8').read()))
+    read('README.md')))
 
-REQUIREMENTS = open('requirements.txt', encoding='utf-8').read().splitlines()
+REQUIREMENTS = read('requirements.txt').splitlines()
 
 
 if sys.argv[1:2] == ['py2exe']:
@@ -34,11 +44,11 @@ if sys.argv[1:2] == ['py2exe']:
         'console': [{
             'script': './yt_dlp/__main__.py',
             'dest_base': 'yt-dlp',
-            'version': __version__,
+            'version': VERSION,
             'description': DESCRIPTION,
             'comments': LONG_DESCRIPTION.split('\n')[0],
             'product_name': 'yt-dlp',
-            'product_version': __version__,
+            'product_version': VERSION,
         }],
         'options': {
             'py2exe': {
@@ -107,7 +117,7 @@ else:
 
 setup(
     name='yt-dlp',
-    version=__version__,
+    version=VERSION,
     maintainer='pukkandan',
     maintainer_email='pukkandan.ytdlp@gmail.com',
     description=DESCRIPTION,