diff --git a/exploration/communication.py b/exploration/expl_communication.py
similarity index 100%
rename from exploration/communication.py
rename to exploration/expl_communication.py
diff --git a/exploration/screen.py b/exploration/expl_screen.py
similarity index 100%
rename from exploration/screen.py
rename to exploration/expl_screen.py
diff --git a/features/communication.py b/features/communication.py
index 6924d42..6a3d8e3 100644
--- a/features/communication.py
+++ b/features/communication.py
@@ -1,4 +1,4 @@
-from typing import List
+from collections.abc import Collection
 
 import pandas as pd
 
@@ -9,7 +9,7 @@ call_types = {1: "incoming", 2: "outgoing", 3: "missed"}
 sms_types = {1: "received", 2: "sent"}
 
 
-def get_call_data(usernames: List) -> pd.DataFrame:
+def get_call_data(usernames: Collection) -> pd.DataFrame:
     """
     Read the data from the calls table and return it in a dataframe.
 
@@ -33,7 +33,7 @@ def get_call_data(usernames: List) -> pd.DataFrame:
     return df_calls
 
 
-def get_sms_data(usernames: List) -> pd.DataFrame:
+def get_sms_data(usernames: Collection) -> pd.DataFrame:
     """
     Read the data from the sms table and return it in a dataframe.
 
diff --git a/features/screen.py b/features/screen.py
index 424c025..d639b45 100644
--- a/features/screen.py
+++ b/features/screen.py
@@ -1,4 +1,4 @@
-from typing import List
+from collections.abc import Collection
 
 import pandas as pd
 
@@ -8,7 +8,7 @@ from setup import db_engine, session
 screen_status = {0: "off", 1: "on", 2: "locked", 3: "unlocked"}
 
 
-def get_screen_data(usernames: List) -> pd.DataFrame:
+def get_screen_data(usernames: Collection) -> pd.DataFrame:
     """
     Read the data from the screen table and return it in a dataframe.
 
diff --git a/test/test_participants.py b/test/test_participants.py
index e449d70..8bbb184 100644
--- a/test/test_participants.py
+++ b/test/test_participants.py
@@ -3,8 +3,8 @@ import unittest
 from participants.query_db import get_usernames
 
 
-class CallsFeatures(unittest.TestCase):
+class ParticipantsQuery(unittest.TestCase):
     def test_get_usernames(self):
         usernames_from_db = get_usernames()
-        print(usernames_from_db)
+        print(type(usernames_from_db))
         self.assertIsNotNone(usernames_from_db)