How do I make a list of tuples into a dictionary without overwriting already existing keys?

Question

I am new to python, and I'm having trouble with my coding.

I have a large text, where every word in this text has gotten a tag (to witch part of speech the words belong).

The tuple looks something like this:

tuple1=[(bag, NN), (run, VB), (window, NN), (act, NN), (act,VB)]

And as you see, the word "act" can be both a verb and a noun. So when I want to make this tuple into a dictionary, I want both {act:NN, act:VB}. I have not managed to do this without overwriting the already existing key.

This is what I have so far:

dicts={}
for i in tuple1:
    dicts[i[0]]=i[1]

ALSO: How can I make every word into either small letters or big letters? So that there is no difference between for example "The" and "the"?

Thanks!

Answer 1

dicts = {}
for key, value in data:
    dicts.setdefault(key,[]).append(value)

returns:

{'bag': ['NN'], 'run': ['VB'], 'window': ['NN'], 'act': ['NN', 'VB']}

Answer 2

dict1 = {}
tuple1 = ((<word>, <type>), ...)

for k, v in tuple1:
    if k in dict1 and v in dict1[k]:
        continue
    elif k not in dict1:
        dict1[k] = [v]
    elif v not in dict1[k]:
        dict1[k].append(v)

Tested with:

(('bag', 'noun'), ('run', 'verb'), ('run', 'noun'), ('act', 'noun'), ('act', 'verb'))

And given output is:

{'bag': ['noun'], 'run': ['verb', 'noun'], 'act': ['noun', 'verb']}

My general idea was that you could simply assign a key to a list which contains the type of word it is and therefore it'd remove any need for adding additional keys with a prefix verb_ or noun_ etc.

On your latter question, to convert a word (string) into either upper or lowercase simply call str.lower() to turn "Hello, world!" into "hello, world!" and str.upper() to turn "hello, world!" into "HELLO, WORLD!"