import sys
import json

# load input arguments from the text file
filename = sys.argv[ 1 ]
with open( filename ) as data_file:   
    input_args = json.loads( data_file.read() )

# cast strings to floats
x, y = [ float(input_args.get( key )) for key in [ 'x', 'y' ] ]

print json.dumps( { 'sum' : x + y , 'subtract' : x - y } )

using MongoDB.Bson;
using System;
using System.Diagnostics;
using System.IO;

namespace python_csharp
{
    class Program
    {
        static void Main(string[] args)
        {
            // full path to .py file
            string pyScriptPath = "...../sum.py";
            // convert input arguments to JSON string
            BsonDocument argsBson = BsonDocument.Parse("{ 'x' : '1', 'y' : '2' }");

            bool saveInputFile = false;
        
            string argsFile = string.Format("{0}\\{1}.txt", Path.GetDirectoryName(pyScriptPath), Guid.NewGuid());

            string outputString = null;
            // create new process start info 
            ProcessStartInfo prcStartInfo = new ProcessStartInfo
            {
                // full path of the Python interpreter 'python.exe'
                FileName = "python.exe", // string.Format(@"""{0}""", "python.exe"),
                UseShellExecute = false,
                RedirectStandardOutput = true,
                CreateNoWindow = false
            };

            try
            {    
                // write input arguments to .txt file 
                using (StreamWriter sw = new StreamWriter(argsFile))
                {
                    sw.WriteLine(argsBson);
                    prcStartInfo.Arguments = string.Format("{0} {1}", string.Format(@"""{0}""", pyScriptPath), string.Format(@"""{0}""", argsFile));
                }
                // start process
                using (Process process = Process.Start(prcStartInfo))
                {
                    // read standard output JSON string
                    using (StreamReader myStreamReader = process.StandardOutput)
                    {
                        outputString = myStreamReader.ReadLine();
                        process.WaitForExit();
                    }
                }
            }
            finally
            {
                // delete/save temporary .txt file 
                if (!saveInputFile)
                {
                    File.Delete(argsFile);
                }
            }
            Console.WriteLine(outputString);
        }
    }
}