Updates plugin path when module loaded.

Signed-off-by: Franco Cipollone <franco.c@ekumenlabs.com>

maliput/__init__.py

@@ -7,3 +7,28 @@
     'math',
     'plugin'
 ]
+
+def get_maliput_backends():
+    import importlib.metadata as importlib_metadata
+    return importlib_metadata.entry_points()['maliput.backends']
+
+# Update MALIPUT_PLUGIN_PATH environment variable with paths provided by the `maliput.backends` entry point
+# Each backend will have as entry point:
+#   group: maliput.backends
+#   name: <backend_name> (e.g. 'maliput_malidrive')
+#   value: method that returns the path to the location of .so files
+def update_plugin_path():
+    import os
+
+    plugin_paths = []
+    for entry_point in get_maliput_backends():
+        plugin_paths.append(entry_point.load()())
+
+    plugin_path = os.pathsep.join(plugin_paths)
+    if 'MALIPUT_PLUGIN_PATH' in os.environ:
+        plugin_path = os.pathsep.join([plugin_path, os.environ['MALIPUT_PLUGIN_PATH']])
+    os.environ['MALIPUT_PLUGIN_PATH'] = plugin_path
+
+
+update_plugin_path()
+