Add check for nmstate C library on pip install

rust/src/python/setup.py

@@ -1,18 +1,52 @@
 # SPDX-License-Identifier: LGPL-2.1-or-later
-
+import ctypes
+import sys
 import setuptools
+import subprocess
 
 
 def requirements():
     req = []
-    with open("requirements.txt") as fd:
+    with open("requirements.txt", encoding="utf-8") as fd:
         for line in fd:
             line.strip()
             if not line.startswith("#"):
                 req.append(line)
     return req
 
 
+def check_nmstate_c_library():
+    if "bdist_rpm" not in sys.argv:
+        try:
+            # Run the find command
+            result = subprocess.run(
+                ["find", "/", "-name", "libnmstate.so.2"],
+                stdout=subprocess.PIPE,
+                stderr=subprocess.PIPE,
+                text=True,
+                check=True,
+            )
+
+            # Check if the command was successful
+            if result.returncode == 0:
+                # Print the result
+                print("-----Found files:\n", result.stdout)
+            else:
+                # Print the error if the command failed
+                print("----The Error is:\n", result.stderr)
+            ctypes.cdll.LoadLibrary("libnmstate.so.2")
+        except OSError as exc:
+            raise RuntimeError(
+                "Error: nmstate C library not found. "
+                "Please install nmstate C library separately "
+                "before installing the Python package."
+                "See: https://nmstate.io/user/install.html"
+            ) from exc
+
+
+check_nmstate_c_library()
+
+
 setuptools.setup(
     name="nmstate",
     version="2.2.32",