Calling a Go function from Python

greet.go

package main
// this example prepared with go version go1.17.1 linux/amd64

import (
	"C"
	"fmt"
)

//export Greet
func Greet(c_target *C.char) *C.char {
	target := C.GoString(c_target)
	greeting := fmt.Sprintf("Hello, %s!", target)
	return C.CString(greeting)
}

func main() {}

main.py

#!/usr/bin/env python3

from ctypes import cdll, c_char_p
import sys

target: str = "world"
if len(sys.argv) > 1:
    target = sys.argv[1]

real_target: c_char_p = c_char_p(target.encode())

lib = cdll.LoadLibrary("./libgreet.so")
lib.Greet.argtypes = [c_char_p]
lib.Greet.restype = c_char_p

greeting: bytes = lib.Greet(real_target)

print(greeting.decode())

Makefile

libgreet.so: greet.go
	go build -o libgreet.so -buildmode=c-shared greet.go

running the examples

# ./main.py 
Hello, world!

# ./main.py zealws
Hello, zealws!