I’m not sure what this means. Are you running Ubuntu Linux (and which version)? Did you follow the steps in Configure Python to use the SNAP-Python (snappy) interface?
Did you generate a jpy binary wheel using your (unspecified) system and python? You should put the jpy binary wheel in your $HOME/.snap/snap-python/snappy directory and then (in a terminal):
$ cd ~/<ESA_snap_install_dir>/nin
$ ./snappy-conf /usr/bin/python3.<minor version>
If this works, continue with the “How to use” steps. Due to the existence of mutliple Python libraries called snappy, I recommend not trying to install ESA SNAP snappy into your system python. If you are comfortable with Python venv’s, you can create a Python “snappy” environment, but for most people it is better to put something like:
sys.path.insert(0,<snappy_dir>)
from snappy import ...
in your scripts so it is clear that the script is using ESA SNAP snappy and also ensure that some other
library called snappy is not used by mistake.