use importlib machinery to check for habana plugin (#1910)

* use importlib machinery to check for habana plugin

Not all environments have pip, and even fewer have grep (e.g. Windows
platforms), and the shell command is relatively costly for
larger environments. Instead, use the stdlib infrastructure with
`importlib` to identify the version of `habana-torch-plugin` if it is
installed.

* use direct import rather than transitive

Author: scw

bitsandbytes/backends/utils.py

@@ -1,4 +1,4 @@
-import subprocess
+from importlib.metadata import metadata
 
 from packaging import version
 import torch
@@ -67,17 +67,16 @@ def get_gaudi_sw_version():
     """
     Returns the installed version of Gaudi SW.
     """
-    output = subprocess.run(
-        "pip list | grep habana-torch-plugin",
-        shell=True,
-        text=True,
-        capture_output=True,
-    )
-    # If grep return nothing
-    if not output.stdout.strip():
-        return None
+    try:
+        # if we find the spec, examine the installed version
+        plugin_metadata = metadata("habana-torch-plugin")
+        plugin_version = plugin_metadata.get("Version")
+        if plugin_version:
+            gaudi_version = version.parse(plugin_version)
+    except Exception:
+        gaudi_version = None
 
-    return version.parse(output.stdout.split("\n")[0].split()[-1])
+    return gaudi_version
 
 
 GAUDI_SW_VER = get_gaudi_sw_version()