Iterate on values/key pairs in Python

I'm learning Python. I know how to do this in JavaScript but I lack the syntax-knowledge at this very moment nor can I find examples that tell me how to do this.

I have the following Array of Objects:

john_williams_compositions = [
{"year": 1973, "Title": "The Poseidon Adventure", "type": "Best Orignal Score", "status": "nominated"},
{"year": 1974, "Title": "Cinderella Liberty", "type": "Best Original Score", "status": "nominated"},
{"year": 1974, "Title": "Tom Sawyer", "type": "Best Original Score", "status": "nominated"},
{"year": 1975, "Title": "Earthquake", "type": "Best Original Score", "status": "nominated"},
{"year": 1976, "Title": "Jaws", "type": "Best Original Score", "status": "Won"},
{"year": 1978, "Title": "Close Encounters of the Third Kind", "type": "Best Original Score", "status": "nominated"},
{"year": 1978, "Title": "Star Wars: Episode IV - A New Hope", "type": "Best Original Score", "status": "Won"},
{"year": 1979, "Title": "Superman", "type": "Best Original Score", "status": "nominated"},
{"year": 1981, "Title": "Star WArs: Episode V - The Empire Strikes Back", "type": "Best Original Score", "status": "nominated"},
{"year": 1983, "Title": "E.T. the Extra Terrestrial", "type": "Best Original Score", "status": "Won"},
{"year": 1983, "Title": "If We Were in Love", "type": "Best Original Song", "status": "nominated"},
{"year": 1985, "Title": "The River", "type": "Best Original Score", "status": "nominated"},
{"year": 1988, "Title": "Empire of the Sun", "type": "Best Original Score", "status": "nominated"}
]

Now I want to get all the objects with the status "Won" in a new array.

I came up with this myself:

def won(list):
result = []
for x in list:
if x.status == "Won":
result.append[i]
return result
print(won(john_williams_compositions))

Can anyone jumpstart me with this?

You can do this very easily with a list comprehension:

def won(lst):
return [comp for comp in lst if comp['status'] == 'Won']
print(won(john_williams_compositions))

Or, alternatively, you can use the filter() function:

def won(lst):
return list(filter(lambda comp: comp['status'] == 'Won', lst))
print(won(john_williams_compositions))

You just need to iterate over the list (of dictionaries) then select those where the status key is equal to Won.

Probably best to write a function that will handle any status value. Something like this:

john_williams_compositions = [
    {"year": 1973, "Title": "The Poseidon Adventure", "type": "Best Orignal Score", "status": "nominated"},
    {"year": 1974, "Title": "Cinderella Liberty", "type": "Best Original Score", "status": "nominated"},
    {"year": 1974, "Title": "Tom Sawyer", "type": "Best Original Score", "status": "nominated"},
    {"year": 1975, "Title": "Earthquake", "type": "Best Original Score", "status": "nominated"},
    {"year": 1976, "Title": "Jaws", "type": "Best Original Score", "status": "Won"},
    {"year": 1978, "Title": "Close Encounters of the Third Kind", "type": "Best Original Score", "status": "nominated"},
    {"year": 1978, "Title": "Star Wars: Episode IV - A New Hope", "type": "Best Original Score", "status": "Won"},
    {"year": 1979, "Title": "Superman", "type": "Best Original Score", "status": "nominated"},
    {"year": 1981, "Title": "Star WArs: Episode V - The Empire Strikes Back", "type": "Best Original Score", "status": "nominated"},
    {"year": 1983, "Title": "E.T. the Extra Terrestrial", "type": "Best Original Score", "status": "Won"},
    {"year": 1983, "Title": "If We Were in Love", "type": "Best Original Song", "status": "nominated"},
    {"year": 1985, "Title": "The River", "type": "Best Original Score", "status": "nominated"},
    {"year": 1988, "Title": "Empire of the Sun", "type": "Best Original Score", "status": "nominated"}
    ]

def get_by_status(lst, status):
    result = []

    for d in lst:
        if d.get('status') == status:
            result.append(d)
            
    return result

print(get_by_status(john_williams_compositions, 'Won'))

Output:

{'year': 1976, 'Title': 'Jaws', 'type': 'Best Original Score', 'status': 'Won'}, {'year': 1978, 'Title': 'Star Wars: Episode IV - A New Hope', 'type': 'Best Original Score', 'status': 'Won'}, {'year': 1983, 'Title': 'E.T. the Extra Terrestrial', 'type': 'Best Original Score', 'status': 'Won'}]

Note: get_by_status() could be implemented as a list comprehension in one line of code. As OP is obviously a beginner, it's written this way for clarity.

def get_by_status(lst, status):
return [d for d in lst if d.get('status') == status]

Since you are a beginner and list comprehension might not look very sraightforward to you, here is a simple implementation:

def won(list):
result = []
for x in list:
if x['status'] == 'Won':
print(x['status'])
result.append(x)
return result
print(won(john_williams_compositions))

x is a dict. Unlike Javascript (I gather), there is a syntactic difference between access the value for a given key in a dict and accessing the value of an attribute.

x["foo"]  # Value associated with key "foo"
x.foo  # Value associated with the attribute "foo"

Your loop requires the former:

def won(list):
result = []
for x in list:
if x["status"] == "Won":
result.append[i]
return result