Django: git push heroku master fail
<p>I am trying to push an django web app to heroku for the first time, and  there are some error message as following.  </p>

<pre><code>Delta compression using up to 4 threads.
Compressing objects: 100% (68/68), done.
Writing objects: 100% (81/81), 105.31 KiB | 0 bytes/s, done.
Total 81 (delta 7), reused 0 (delta 0)
remote: Compressing source files... done.
remote: Building source:
remote:
remote: -----&gt; Python app detected
remote: -----&gt; Installing Python-3.5.0
remote:  !     Requested runtime (Python-3.5.0) is not available for this     stack
(cedar-14).
remote:  !     Aborting.  More info:     https://devcenter.heroku.com/articles/pytho
n-support
remote:
remote:  !     Push rejected, failed to compile Python app
remote:
remote: Verifying deploy...
remote:
remote: !       Push rejected to polar-lake-12528.
remote:
To https://git.heroku.com/polar-lake-12528.git
 ! [remote rejected] master -&gt; master (pre-receive hook declined)
error: failed to push some refs to 'https://git.heroku.com/polar-lake-12528.git'
</code></pre>

<p>My runtime.txt looks like: </p>

<pre><code>python-3.5.1
</code></pre>

<p>I have already changed to lowercase and update the version of python to 3.5.1, but still not working.</p>