[HOTFIX][ZEPPELIN-1656] z.show in Python interpreter does not work

[agoodm]

What is this PR for?

There have been reports of #1534 causing the python interpreter to always show an error because z is not being set. As it turns out this is a result of improperly handling the case when matplotlib isn't found when initializing the interpreter.

What type of PR is it?

Bug Fix

What is the Jira issue?

ZEPPELIN-1656

How should this be tested?

Run any simple python paragraph.

Questions:

• Does the licenses files need update? No
• Is there breaking changes for older versions? No
• Does this needs documentation? No

[agoodm]

@bzz please test ASAP!

[bzz]

Will test right now and post back

[bzz]

Tested with and without matplotlib - both cases work fine!

Also

%python
a = 'a'
print "{}".format(a)

works as expected as well!

👍 thank you for prompt fix, looks awesome to me, will merge to master as hotfix asap, if there is no further discussion