Example:
>>> from django.http import QueryDict
>>> q = QueryDict('a=x&b=y&c=z')
>>> q
<QueryDict: {u'a': [u'x'], u'c': [u'z'], u'b': [u'y']}>
>>> q = QueryDict('a=x&b=y&c=z+1')
>>> q
<QueryDict: {u'a': [u'x'], u'c': [u'z 1'], u'b': [u'y']}>
>>> ^
Why is the '+' replaced with a space?