In Python, how do I loop through the dictionary and change the value if it equals something?

for k, v in mydict.iteritems():
    if v is None:
        mydict[k] = ''

In a more general case, e.g. if you were adding or removing keys, it might not be safe to change the structure of the container you’re looping on — so using items to loop on an independent list copy thereof might be prudent — but assigning a different value at a given existing index does not incur any problem, so, in Python 2.any, it’s better to use iteritems.

In Python3 however the code gives AttributeError: 'dict' object has no attribute 'iteritems' error. Use items() instead of iteritems() here.

Refer to this post.