>>> d1 = {'a':2, 'b':3}
>>> d2 = eval(repr(d1))
>>> d2
{'a': 2, 'b': 3}
>>> d2['c']=1
>>> d1
{'a': 2, 'b': 3}
>>> d2
{'a': 2, 'c': 1, 'b': 3}

def read_from_file():
   after_d = {}
   fp = open("test.txt", "r")
   for rec in fp:
      rec=rec.strip()
      key, name = rec.split(";")
      after_d[int(key)]=name        ## convert key back to an integer
   fp.close()
   return after_d
 
 
def save_to_file(save_d):
   print "before saving to file", save_d
   fp = open("test.txt", "w")
   for key in save_d.keys():
      fp.write("%d;%s\n" % (key, save_d[key]))  ## writes everything as a string
   fp.close()
 
 
before_d = {}
before_d[1]="Name 1"
before_d[2]="Name 2"
before_d[3]="Name 3"
before_d[10]="Name 10"
before_d[20]="Name 20"
 
save_to_file(before_d)
after = read_from_file()
print "read from file       ", after

# use module pickle to save/dump and load a dictionary object
# or just about any other intact object
 
import pickle
 
# create the test dictionary
before_d = {}
before_d[1]="Name 1"
before_d[2]="Name 2"
before_d[3]="Name 3"
 
# pickle dump the dictionary
fout = open("dict1.dat", "w")
pickle.dump(before_d, fout)
fout.close()
 
# pickle load the dictionary
fin = open("dict1.dat", "r")
after_d = pickle.load(fin)
fin.close()
 
print before_d  # {1: 'Name 1', 2: 'Name 2', 3: 'Name 3'}
print after_d   # {1: 'Name 1', 2: 'Name 2', 3: 'Name 3'}