Create unit8_ex8.3.4.py

lironmiz · web-flow · commit af8332e5bd76 · 2023-01-05T05:31:47.000+02:00
diff --git a/unit8_ex8.3.4.py b/unit8_ex8.3.4.py
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+# exercies 8.3.4 from unit 8
+'''
+We are nearing the end of the course and at this stage you can combine the topics
+learned throughout the course, explore additional options yourself and apply everything
+in writing the code.
+
+In this exercise, write a function called inverse_dict defined as follows:
+
+def inverse_dict(my_dict):
+The function accepts as a parameter a dictionary.
+The function returns a new dictionary with a "reverse" mapping: each key in the passed
+dictionary is a value in the returned dictionary and each value in the passed dictionary 
+is a key in the returned dictionary.
+
+Guidelines
+
+The inversion between keys and values may create keys that appear more than once. Therefore,
+display the values in the returned dictionary as a list, which may contain one or more values
+The returned lists should be sorted (it can be assumed that the values in the dictionary
+are of the same type).
+
+'''
+
+def main():
+    def inverse_dict_helper(my_dict):
+        inverted_dict = {}
+        for key, value in my_dict.items():
+            if value not in inverted_dict:
+                inverted_dict[value] = [key]
+            else:
+                inverted_dict[value].append(key)
+        for value in inverted_dict.values():
+            value.sort()
+        return inverted_dict
+
+    my_dict = {'a': 1, 'b': 2, 'c': 1, 'd': 2, 'e': 2}
+    print(inverse_dict_helper(my_dict))
+
+main()
+
