Java libraries in scripts

Hello.

I'm trying to import a jar file in a script but it doesn't work:
For example:

1- sys.path.append( "<pathtojar>/commons-math3-3.6.1.jar" )
2-
3- from org.apache.commons.math3.analysis import FunctionUtils

And the error that I get is:

ImportError: No module named apache in <script> at line number 3
Traceback (most recent call last):
File "<script>", line 3, in <module>
ImportError: No module named apache

What's wrong with the code?

Thanks.