First attempts
OMG! My weird code works! (P.S. Week ago I didn't know Python exists)
import string
punct = set(string.punctuation + string.digits)
longest = None
shortest = None
text = raw_input('Enter some text:')
free_text = ''.join(x for x in text if x not in punct)
words = free_text.split()
number = len(words)
total = 0
for word in words:
summa = total + len(word)
total = summa
while longest is None or len(word) > len(longest):
longest = word
while shortest is None or len(word) < len(shortest):
shortest = word
if number < 1:
print 'number of words:', number
print 'end of program'
else:
print 'number of letters:', summa
print 'number of words:', number
print 'longest word is:', longest, ',', len(longest)
print 'shortest word is:', shortest, ',', len(shortest)
print 'avarage word lenght is:', float(summa)/number
print 'end of program'