Fixed how setup.py is written out after updating

Author: Justin Boswell

continuous-delivery/update-version.py

@@ -9,11 +9,14 @@
 version = str(tag[1:].strip(), 'utf8')
 setup_path = os.path.join(os.path.dirname(__file__), '..', 'setup.py')
 print("Updating setup.py to version {}".format(version))
+contents = None
 with open(setup_path, 'r+') as setup_py:
     contents = setup_py.read()
-    contents = re.sub(r'(\s)version="1\.0\.0-dev",', r'\1version="{}",'.format(version), contents)
-    setup_py.seek(0)
+
+contents = re.sub(r'(\s)version="1\.0\.0-dev",', r'\1version="{}",'.format(version), contents)
+
+with open(setup_path, 'w') as setup_py:
     setup_py.write(contents)
 
-    setup = contents[contents.rfind('setuptools.setup'):]
-    print(setup)
+setup = contents[contents.rfind('setuptools.setup'):]
+print(setup)