Python-сообщество

>>> 'aaabbcbdcaasa'.count('a')
6
>>> sorted([3,4,2,1,8,5])
[1, 2, 3, 4, 5, 8]

# -*- coding:utf-8 -*-
from collections import Counter
class StringWithCounter():
  class Getter(object):
    
    def __init__(self, _string):
      self.c=Counter(_string)
    
    def __getattr__(self, attr):
      if len(attr)>1:
	raise Exception(u'The function only accepts letters, not a strings')
      return self.c[attr]
    
   
  def __init__(self, _string):
    self.string=_string
      
  def __setattr__(self, attr, value):
    if attr == 'string':
       self.get_a_count=self.Getter(value)
    self.__dict__[attr]=value
    
s=StringWithCounter('dfsdfsdfsdfsdf')
print s.get_a_count.d
s.string="ooooooooooooooooooooooo"
print s.get_a_count.o