def read_words(filename):
    """Return a dictionary mapping each word in filename
    to its frequency in the file"""
    wordfile = open(filename)
    worddata = wordfile.read()
    words = worddata.split()
    wordfile.close()
    wordcounts = {}
    for w in words:
        cnt = wordcounts.setdefault(w, 0)
        wordcounts[w] = cnt + 1
    return wordcounts

def wordcount(wordcounts, word):
    """Return the count of the given word in wordcounts"""
    if wordcounts.has_key(word):
        return wordcounts[word]
    else:
        return 0

def topk(wordcounts, k=10):
    """Return top k most frequent words in wordcount
    If less then k unique words in wordcount, return all words."""
    scores_with_words = [(c,w) for (w,c) in wordcounts.items()]
    scores_with_words.sort(reverse=True)
    return scores_with_words[0:k]

def totalwords(wordcounts):
    """Return the total number of words in the file"""
    return sum([c for (w,c) in wordcounts.items()])


wordcounts = read_words("foo2.txt")
print "wordcounts :", wordcounts
k = 1
print "top", k, " :", topk(wordcounts, k)
print "top 10 :", topk(wordcounts)
print "total words in file:", totalwords(wordcounts)
print "count of quick:", wordcount(wordcounts, "quick")
print "count of foo:", wordcount(wordcounts, "foo")