The question requires knowledge of python programming.

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i) Implement a function in Python to create a dictionary: { 'a': 10, 'b': 20, 'c': 30, 'd': 40} and display each key-value pairs of it. (5 marks) Implement a function dict_check_add(dictionary, key, value) in Python to check whether a key of the given key-value pair already exists in the dictionary. If it is not, add the key-value pair to the dictionary