Added support for externally set netron port and localhost_url, as well as a doc-string.

src/finn/util/visualization.py

@@ -36,7 +36,29 @@ def showSrc(what):
     print("".join(inspect.getsourcelines(what)[0]))
 
 
-def showInNetron(model_filename):
-    netron.start(model_filename, address=("0.0.0.0", 8081))
-    localhost_url = os.getenv("LOCALHOST_URL", default="localhost")
-    return IFrame(src="http://%s:8081/" % localhost_url, width="100%", height=400)
+def showInNetron(model_filename: str, localhost_url: str = None, port: int = None):
+    """Shows a ONNX model file in the Jupyter Notebook using Netron.
+
+    :param model_filename: The path to the ONNX model file.
+    :type model_filename: str
+
+    :param localhost_url: The IP address used by the Jupyter IFrame to show the model.
+     Defaults to localhost.
+    :type localhost_url: str, optional
+
+    :param port: The port number used by Netron and the Jupyter IFrame to show
+     the ONNX model.  Defaults to 8081.
+    :type port: int, optional
+
+    :return: The IFrame displaying the ONNX model.
+    :rtype: IPython.lib.display.IFrame
+    """
+    if port is None:
+        try:
+            port = int(os.environ["NETRON_PORT"])
+        except KeyError:
+            port = 8081
+    if localhost_url is None:
+        localhost_url = os.getenv("LOCALHOST_URL", default="localhost")
+    netron.start(model_filename, address=("0.0.0.0", port), browse=False)
+    return IFrame(src=f"http://{localhost_url}:{port}/", width="100%", height=400)