Write a function called count_words. This function is passed the name of a file, and should count the number of times each word occurs in the file. A dictionary should be returned, whose keys are words, and whose values are their counts. For example:

>>> freq = count_words('hamlet.txt') >>> freq['to'] 13

>>> freq['be'] 3 >>> freq['or'] 2 

>>> freq['hamlet'] 

Traceback (most recent call last): File "", line 1, in 

 freq['hamlet'] KeyError: 'hamlet'