pdflatex not available from Jupyter in SageMath-8.1.app

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I am using SageMath-8.1.app with OSX 10.13.5 and pdflatex is available on my system:

(sage-sh) :SageMath-8.1.app$ which pdflatex
/Library/TeX/texbin/pdflatex

But in Jupyter, pdf latex is not available:

view(g)
Error: PDFLaTeX does not seem to be installed.  Download it from
ctan.org and try again.
Latex error

also:

!pdflatex
/bin/sh: pdflatex: command not found

Here is the value of PATH:

import os
os.environ['PATH']
'/Applications/SageMath-8.1.app/Contents/Resources/sage/local/libexec/ccache:/Applications/SageMath-8.1.app/Contents/Resources/sage/build/bin:/Applications/SageMath-8.1.app/Contents/Resources/sage/src/bin:/Applications/SageMath-8.1.app/Contents/Resources/sage/local/bin:/usr/bin:/bin:/usr/sbin:/sbin'

How to modify the PATH of the app?