Bugfix, update rsa's library name

[llliuyx]

error: Could not find suitable distribution for Requirement.parse('python-rsa')

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[coveralls]

Coverage remained the same at 42.384% when pulling 1e837f9 on llliuyx:master into 21c6a7c on google:master.

[coveralls]

Coverage remained the same at 42.384% when pulling 1e837f9 on llliuyx:master into 21c6a7c on google:master.

[fahhem]

Once you sign the CLA I can merge this in

[llliuyx]

I signed it!

[googlebot]

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