How do I modify a dict locally as to not effect the global variable in python

Question

How do I create a dictionary in python that is passed to a function so it would look like this:

def foobar(dict):
    dict = tempdict # I want tempdict to not point to dict, but to be a different  dict
    #logic that modifies tempdict
    return tempdict

How do I do this?

Answer 1

You need to copy dict to tempdict.

def foobar(d):
    temp = d.copy()
    # your logic goes here
    return temp

copy makes a shallow copy of the dict (i.e. copying its values, but not its values' values).

% python
Python 2.6.5 (r265:79063, Apr 16 2010, 13:09:56) 
[GCC 4.4.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> d = {'x': 17, 'y': 23}
>>> t = d.copy()
>>> t
{'y': 23, 'x': 17}
>>> t['x'] = 93
>>> t
{'y': 23, 'x': 93}
>>> d
{'y': 23, 'x': 17}
>>>