diff --git a/lobster/tools/coda/coda.py b/lobster/tools/coda/coda.py
index 63ca180d..5f33ec58 100644
--- a/lobster/tools/coda/coda.py
+++ b/lobster/tools/coda/coda.py
@@ -88,35 +88,36 @@ def parse_config_file(file_name: str) -> dict:
         or contains not supported values.
     """
     if not os.path.isfile(file_name):
-        raise Exception(f'{file_name} is not an existing file!')
+        raise ValueError(f'{file_name} is not an existing file!')
 
-    with open(file_name, "r") as file:
+    with open(file_name, "r", encoding='utf-8') as file:
         config_dict: dict = json.loads(file.read())
 
     if OUTPUT not in config_dict.keys():
-        raise Exception(f'Please follow the right config file structure! '
-                        f'Missing attribute "{OUTPUT}"')
+        raise ValueError(f'Please follow the right config file structure! '
+                         f'Missing attribute "{OUTPUT}"')
 
     output_config_dict = config_dict.get(OUTPUT)
 
     supported_markers = ', '.join(SUPPORTED_REQUIREMENTS)
     for output_file, output_file_config_dict in output_config_dict.items():
         if MARKERS not in output_file_config_dict.keys():
-            raise Exception(f'Please follow the right config file structure! '
-                            f'Missing attribute "{MARKERS}" for output file '
-                            f'"{output_file}"')
+            raise ValueError(f'Please follow the right config file structure! '
+                             f'Missing attribute "{MARKERS}" for output file '
+                             f'"{output_file}"')
         if KIND not in output_file_config_dict.keys():
-            raise Exception(f'Please follow the right config file structure! '
-                            f'Missing attribute "{KIND}" for output file '
-                            f'"{output_file}"')
+            raise ValueError(f'Please follow the right config file structure! '
+                             f'Missing attribute "{KIND}" for output file '
+                             f'"{output_file}"')
 
         output_file_marker_list = output_file_config_dict.get(MARKERS)
         for output_file_marker in output_file_marker_list:
             if output_file_marker not in SUPPORTED_REQUIREMENTS:
-                raise Exception(f'"{output_file_marker}" is not a supported '
-                                f'"{MARKERS}" value '
-                                f'for output file "{output_file}". '
-                                f'Supported values are: "{supported_markers}"')
+                raise ValueError(f'"{output_file_marker}" is not a supported '
+                                 f'"{MARKERS}" value '
+                                 f'for output file "{output_file}". '
+                                 f'Supported values are: '
+                                 f'"{supported_markers}"')
 
     return config_dict
 
@@ -162,10 +163,10 @@ def get_test_file_list(file_dir_list: list, extension_list: list) -> list:
                     if ext in extension_list:
                         test_file_list.append(os.path.join(path, filename))
         else:
-            raise Exception(f'"{file_dir_entry}" is not a file or directory.')
+            raise ValueError(f'"{file_dir_entry}" is not a file or directory.')
 
     if len(test_file_list) == 0:
-        raise Exception(f'"{file_dir_list}" does not contain any test file.')
+        raise ValueError(f'"{file_dir_list}" does not contain any test file.')
 
     return test_file_list
 
@@ -225,7 +226,7 @@ def create_lobster_items_output_dict_from_test_cases(
         else:
             no_marker_output_file_name = output_file_name
 
-    if no_marker_output_file_name not in lobster_items_output_dict.keys():
+    if no_marker_output_file_name not in lobster_items_output_dict:
         lobster_items_output_dict[no_marker_output_file_name] = {}
 
     for test_case in test_case_list:
@@ -253,7 +254,7 @@ def create_lobster_items_output_dict_from_test_cases(
             tracing_target_list = []
             tracing_target_kind = output_config_dict.get(KIND)
             for marker in output_config_dict.get(MARKERS):
-                if marker not in map_test_type_to_key_name.keys():
+                if marker not in map_test_type_to_key_name:
                     continue
 
                 for test_case_marker_value in getattr(
@@ -382,7 +383,7 @@ def main():
             config_dict=config_dict
         )
 
-    except Exception as exception:
+    except ValueError as exception:
         ap.error(exception)