Python – Flask: Is it possible to return a collection as a JSON response

While using Flask, can I return a set as JSON response from the REST endpoint?

For example:

@app.route('/test')
def test():

list = [1, 1, 1, 1, 2, 2, 2, 2, 3, 4, 4]

unique_list = set(list)

return json.dumps(unique_list)

I’ve tried it but I get the following error:

TypeError: unhashable type: 'list'

I’ve also tried turning the collection back into a list and returning it. But I’m getting the same error as above.

Any ideas?

jsonify with flask returns a JSON response. Also, don’t use list as a variable name and convert the unique set back to list.

from flask import jsonify

@app.route('/test')
def test():

my_list = [1, 1, 1, 1, 2, 2, 2, 2, 3, 4, 4]

unique_list = list(set(my_list))

return jsonify(results=unique_list)