diff --git a/week05-testing/test_times.py b/week05-testing/test_times.py
new file mode 100644
index 0000000..40de8b6
--- /dev/null
+++ b/week05-testing/test_times.py
@@ -0,0 +1,10 @@
+from times import compute_overlap_time, time_range
+
+def test_given_input():
+
+    range1 = time_range("2010-01-12 10:00:00", "2010-01-12 12:00:00")
+    range2 = time_range("2010-01-12 10:30:00", "2010-01-12 10:45:00", 2, 60)
+    result = compute_overlap_time(range1, range2) 
+    expected = [('2010-01-12 10:30:00', '2010-01-12 10:37:00'), ('2010-01-12 10:38:00', '2010-01-12 10:45:00')]
+    assert result == expected
+
diff --git a/week05-testing/times.py b/week05-testing/times.py
new file mode 100644
index 0000000..3226477
--- /dev/null
+++ b/week05-testing/times.py
@@ -0,0 +1,33 @@
+import datetime
+
+
+# gives the time range between start time and end time [t1, t2] and [t3,t3]
+# d is the time difference
+# sec_range gives the difference interval in seconds 
+# number of intervals [t2,t3]
+def time_range(start_time, end_time, number_of_intervals=1, gap_between_intervals_s=0): # what's intervals?
+    start_time_s = datetime.datetime.strptime(start_time, "%Y-%m-%d %H:%M:%S") # from date string to datetime objects 
+    end_time_s = datetime.datetime.strptime(end_time, "%Y-%m-%d %H:%M:%S") # from date string to datetime objects
+    d = (end_time_s - start_time_s).total_seconds() / number_of_intervals + gap_between_intervals_s * (1 / number_of_intervals - 1) 
+    sec_range = [(start_time_s + datetime.timedelta(seconds=i * d + i * gap_between_intervals_s),
+                  start_time_s + datetime.timedelta(seconds=(i + 1) * d + i * gap_between_intervals_s))
+                 for i in range(number_of_intervals)]
+    return [(ta.strftime("%Y-%m-%d %H:%M:%S"), tb.strftime("%Y-%m-%d %H:%M:%S")) for ta, tb in sec_range] 
+    # from object datetime to string - output: 7200sec 
+
+# gives the overlap time between range 1 [1,t2] and range 2 [t3,t4]
+def compute_overlap_time(range1, range2):
+    overlap_time = []
+    for start1, end1 in range1:
+        for start2, end2 in range2:
+            low = max(start1, start2)
+            high = min(end1, end2)
+            overlap_time.append((low, high))
+    return overlap_time
+
+if __name__ == "__main__":
+    large = time_range("2010-01-12 10:00:00", "2010-01-12 12:00:00") # range 1 [t1,t2]
+    short = time_range("2010-01-12 10:30:00", "2010-01-12 10:45:00", 2, 60) # range 2 [t3,t4]
+    print(large)
+    print(short)
+    print(compute_overlap_time(large, short))
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