For SNAP 10 the toolboxes are thematically reorganised.
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In SNAP 10, the access to SNAP from Python is provided by an external plugin ‘esa_snappy'. This plugin basically contains the functionalities of the previous ‘snappy’ module in SNAP versions <= 9. The plugin works with the standard CPython, so that any native Python extension modules such as numpy and scipy can be used. The esa_snappy module depends on a bi-directional Java-Python bridge jpy that enables calls from Python into a Java virtual machine and, at the same time, the other way round. This bridge is implemented by the jpy Project and is independent from the esa_snappy module.
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Guidelines how to access, install and use esa_snappy are given in the corresponding doumentation Configure Python to use the new SNAP-Python (esa_snappy) interface (SNAP version 10+) and How to use the SNAP API from Python.