pyinit — Initialize the Python interpreter.
In the command-line version of Csound, you must first invoke the pyinit opcode in the orchestra header to initialize the Python interpreter, before using any of the other Python opcodes.
But if you use the Python opcodes in the CsoundVST version of Csound, you need not invoke pyinit, because CsoundVST automatically initializes the Python interpreter for you. In addition, CsoundVST automatically creates a Python interface to the Csound API, in the form a global instance of the CsoundVST.CppSound class named csound. Therefore, Python code written in the Csound orchestra has access to the global csound object.