diff --git a/README.md b/README.md
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diff --git a/closures.py b/closures.py
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diff --git a/cpu_time.py b/cpu_time.py
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diff --git a/diff_files.py b/diff_files.py
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+# Sebastian Raschka, 2014
+#
+# Print lines that are different between 2 files. Insensitive
+# to the order of the file contents.
+
+id_set1 = set()
+id_set2 = set()
+
+with open('id_file1.txt', 'r') as id_file:
+    for line in id_file:
+        id_set1.add(line)
+
+with open('id_file2.txt', 'r') as id_file:
+    for line in id_file:
+        id_set2.add(line)    
+
+diffs = id_set2.difference(id_set1)
+
+for d in diffs:
+    print(d)
+print("Total differences:",len(diffs))
diff --git a/get_filename.py b/get_filename.py
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diff --git a/pickle_module.py b/pickle_module.py
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diff --git a/read_file.py b/read_file.py
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