fix: Remove ResourceWarning on module import (#128)

* Fix ResourceWarning on module import

* Fix ResourceWarning in setup.py

Author: connesy

python_http_client/__init__.py

@@ -19,4 +19,5 @@
 
 dir_path = os.path.dirname(os.path.realpath(__file__))
 if os.path.isfile(os.path.join(dir_path, 'VERSION.txt')):
-    __version__ = open(os.path.join(dir_path, 'VERSION.txt')).read().strip()
+    with open(os.path.join(dir_path, 'VERSION.txt')) as version_file:
+        __version__ = version_file.read().strip()

setup.py

@@ -5,9 +5,10 @@
 
 
 dir_path = os.path.abspath(os.path.dirname(__file__))
-readme = io.open(os.path.join(dir_path, 'README.rst'), encoding='utf-8').read()
-version = io.open(os.path.join(dir_path, 'VERSION.txt'),
-                  encoding='utf-8').read().strip()
+with io.open(os.path.join(dir_path, 'README.rst'), encoding='utf-8') as readme_file:
+    readme = readme_file.read()
+with io.open(os.path.join(dir_path, 'VERSION.txt'), encoding='utf-8') as version_file:
+    version = version_file.read().strip()
 base_url = 'https://github.com/sendgrid/'
 
 copy_file(os.path.join(dir_path, 'VERSION.txt'),