Write a function wordFrequency(text) that computes a dictionary containing the frequency of each word in the string text. For example, wordFrequency('I am I.') should return the dictionary {'I': 2, 'am': 1}. (Hint: the split and strip string methods will be useful, as you need to remove punctuation; use split first, then strip on each word in the resulting list). Once you have computed the dictionary D, return [D], i.e. return a one-item list containing the dictionary D. Without this, codingbat doesn't know how to check correctness.