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 CsoundAC version of
      Csound, you need not invoke pyinit, because CsoundAC automatically
      initializes the Python interpreter for you. In addition, CsoundAC
      automatically creates a Python interface to the Csound API, in the
      form a global instance of the CsoundAC.CppSound class named
      csound. Therefore, Python code written in the Csound orchestra has
      access to the global csound object.