title: call a Python function from c++ using pybind11
body: <p>I am trying to call a python function from a C++ code which contains <code>main()</code> function using <code>Pybind11</code>. But I found very few references are available. Most of existing documents talk about the reversed direction, i.e. calling C++ from Python.</p>
  
  <p>Is there any complete example showing how to do that? The only reference I found is: <a href="https://github.com/pybind/pybind11/issues/30" rel="noreferrer">https://github.com/pybind/pybind11/issues/30</a> </p>
  
  <p>But it has very little information.</p>