We have 1) script sends many dicts
my_data = ({'key1':['test1', 'test2', ['test3', 23]]})
r = requests.post('http://127.0.0.1:5000/', data = my_data)
2) server
@app.route('/', methods=['GET', 'POST'])
def server_main():
data = request.form.to_dict(flat=False) #this works, but with some issues, if dict.values() has lists
data = # your ideas?