Python-сообщество

elem = my_dict[ "key" ]

def __init__(self, buf = ''):
        # Force self.buf to be a string or unicode
        if not isinstance(buf, basestring):
            buf = str(buf)
        self.buf = buf
        self.len = len(buf)
        self.buflist = []
        self.pos = 0
        self.closed = False
        self.softspace = 0

def write(self, s):
        """Write a string to the file.

        There is no return value.
        """
        _complain_ifclosed(self.closed)
        if not s: return
        # Force s to be a string or unicode
        if not isinstance(s, basestring):
            s = str(s)
        spos = self.pos
        slen = self.len
        if spos == slen:
            self.buflist.append(s)
            self.len = self.pos = spos + len(s)
            return
        if spos > slen:
            self.buflist.append('\0'*(spos - slen))
            slen = spos
        newpos = spos + len(s)
        if spos < slen:
            if self.buflist:
                self.buf += ''.join(self.buflist)
            self.buflist = [self.buf[:spos], s, self.buf[newpos:]]
            self.buf = ''
            if newpos > slen:
                slen = newpos
        else:
            self.buflist.append(s)
            slen = newpos
        self.len = slen
        self.pos = newpos

d = {}
d[`key1`]=['чтототам1'] #исправлено - список вместо кортежа, т.к. кортежи не переприсваиваются
d[`key2`]=['чтототам2']
d[`key3`]=['чтототам3']
o = d[`key3`]
и дальше все операции с
o[0]

или через свойства класса

class ChtotoTam:
    __init__(self,attribute='')
        self.attribute=attribute

d = {}
d[`key1`]=ChtotoTam('чтототам1')
d[`key2`]=ChtotoTam('чтототам2')
d[`key3`]=ChtotoTam('чтототам3')
o = d[`key3`]

и дальше все операции с
o.attribute

from cStringIO import StringIO
buf_size = 1024
buf = StringIO( "\0" * buf_size )
buf.seek(0)

def seek(self, pos, mode = 0):
        """Set the file's current position.

        The mode argument is optional and defaults to 0 (absolute file
        positioning); other values are 1 (seek relative to the current
        position) and 2 (seek relative to the file's end).

        There is no return value.
        """
        _complain_ifclosed(self.closed)
        if self.buflist:
            self.buf += ''.join(self.buflist)
            self.buflist = []
        if mode == 1:
            pos += self.pos
        elif mode == 2:
            pos += self.len
        self.pos = max(0, pos)