Python – Using pickle.dump – TypeError: must be str, not bytes

picklepythonpython-3.x

I'm using python3.3 and I'm having a cryptic error when trying to pickle a simple dictionary.

Here is the code:

import os
import pickle
from pickle import *
os.chdir('c:/Python26/progfiles/')

def storvars(vdict):      
    f = open('varstor.txt','w')
    pickle.dump(vdict,f,)
    f.close()
    return

mydict = {'name':'john','gender':'male','age':'45'}
storvars(mydict)

and I get:

Traceback (most recent call last):
  File "C:/Python26/test18.py", line 31, in <module>
    storvars(mydict)
  File "C:/Python26/test18.py", line 14, in storvars
    pickle.dump(vdict,f,)
TypeError: must be str, not bytes

Best Answer

The output file needs to be opened in binary mode:

f = open('varstor.txt','w')

needs to be:

f = open('varstor.txt','wb')

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Python – Using global variables in a function

You can use a global variable within other functions by declaring it as global within each function that assigns a value to it:

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Python – builtins.TypeError: must be str, not bytes

The outfile should be in binary mode.

outFile = open('output.xml', 'wb')

Best Answer

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