Question

How can I solve this in Python?

Please enter a string of text (the bigger the better): The rain in Spain stays mainly in the plain.
The distribution of characters in “The rain in Spain stays mainly in the plain.” is:

iiiiii
nnnnnn
aaaaa
sss
ttt
ee
hh
ll
pp
yy
m
r

Answer 1

This prints that exact output:

dist={}
ex='The rain in Spain stays mainly in the plain.'
for ch in ex.lower():
    if ch.isalpha(): dist.setdefault(ch,[]).extend(ch)

out={k:''.join(val) for k,val in dist.iteritems()}.values()
print '\n'.join(sorted(out, key=lambda x: (-len(x),x)))

prints:

iiiiii
nnnnnn
aaaaa
sss
ttt
ee
hh
ll
pp
yy
m
r