[ZEPPELIN-2132] PySpark: Printing javascript via %htm executes Javascript twice - ASF JIRA

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If you use %html to print javascript (e.g. in order to embed visualisation library output from Bokeh), the javascript gets executed twice:

%pyspark

print("%html")
print("""
<script>
  console.log('test');
</script>
""")

Javascript Console in browser:

(2) test

with (2) being the badge in the console that flags the number of same outputs.

This sometimes leads to strange behaviour if a library assumes the conde runs exactly once.