shelve

import shelve  d = shelve.open(filename) # open -- file may get suffix added by low-level                           # library  d[key] = data   # store data at key (overwrites old data if                 # using an existing key) data = d[key]   # retrieve a COPY of data at key (raise KeyError if no                 # such key) del d[key]      # delete data stored at key (raises KeyError                 # if no such key) flag = d.has_key(key)   # true if the key exists klist = d.keys() # a list of all existing keys (slow!)  # as d was opened WITHOUT writeback=True, beware: d['xx'] = range(4)  # this works as expected, but... d['xx'].append(5)   # *this doesn't!* -- d['xx'] is STILL range(4)!  # having opened d without writeback=True, you need to code carefully: temp = d['xx']      # extracts the copy temp.append(5)      # mutates the copy d['xx'] = temp      # stores the copy right back, to persist it  # or, d=shelve.open(filename,writeback=True) would let you just code # d['xx'].append(5) and have it work as expected, BUT it would also # consume more memory and make the d.close() operation slower.  d.close()       # close it