Better Python 3 support

[streeter]

No description provided.

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[streeter]

I signed it!

[googlebot]

CLAs look good, thanks!

[erlichmen]

Committers, pls expect this PR py3 support is really needed.

[BrandonY]

Looks good to me.

[rajasimon]

This is not available in googleappenginecloudstorageclient==1.9.22.1 release right ? Then when do I expect this ?

It 's so hard to deploy without that I'm running on Python3.6 Flexible appengine. Help me here.

[frankyn]

@rajasimon, IIUC, you're running Python 3.6 on Google Appengine flexible environment. If this is correct, you should use the Google Cloud Python client library and not this Appengine GCS client library as it's meant for Google Appengine standard environment.

[rajasimon]

Thanks for your response. I started using Google cloud python client library.