Minor fixes for typos and bugs (#58)

* change default value for extra_config

* fix typo

Author: lolipopshock

src/layoutparser/models/detectron2/layoutmodel.py

@@ -56,10 +56,13 @@ def __init__(
         config_path,
         model_path=None,
         label_map=None,
-        extra_config=[],
+        extra_config=None,
         enforce_cpu=False,
     ):
 
+        if extra_config is None:
+            extra_config = []
+
         if config_path.startswith("lp://") and label_map is None:
             dataset_name = config_path.lstrip("lp://").split("/")[0]
             label_map = LABEL_MAP_CATALOG[dataset_name]

src/layoutparser/models/paddledetection/layoutmodel.py

@@ -96,8 +96,12 @@ def __init__(
         model_path=None,
         label_map=None,
         enforce_cpu=False,
-        extra_config={},
+        extra_config=None,
     ):
+    
+        if extra_config is None:
+            extra_config = {}
+
         if model_path is not None:
             model_dir = model_path
         elif config_path is not None and config_path.startswith(

src/layoutparser/visualization.py

@@ -159,7 +159,7 @@ def draw_box(
             Whether to display `block.id` on the top-left corner of
             the block.
             Defaults to False.
-        show_element_id (bool, optional):
+        show_element_type (bool, optional):
             Whether to display `block.type` on the top-left corner of
             the block.
             Defaults to False.