updated classifier

Author: flexatone

setup.py

@@ -52,7 +52,7 @@ def get_ext_dir(*components: tp.Iterable[str]) -> tp.Sequence[str]:
     license='MIT',
     # See https://pypi.python.org/pypi?%3Aaction=list_classifiers
     classifiers=[
-        'Development Status :: 3 - Alpha',
+        'Development Status :: 5 - Production/Stable',
         'Intended Audience :: Developers',
         'Topic :: Software Development',
         'License :: OSI Approved :: MIT License',