Александр

https://pkk.rosreestr.ru/api/features/?text=52.929979122449325+87.97534995053527&tolerance=2&types=[2,3,4,1,21,5,10]

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>>> import itertools
>>> a = "1\n2\n3\n4\n5".split("\n")
>>> ["\n".join(filter(lambda x:x!=None,list(x))) for x in itertools.zip_longest(a[::2],a[1::2])]
['1\n2', '3\n4', '5']

yourlist=mylist.split("\n")
firstpart, secondpart = "\n".join(yourlist[:len(yourlist)//2]), "\n".join(yourlist[len(yourlist)//2:])

import json
data = {'1':2,'2':3,'3':'Тестовый JSON'}
json.dump(data, open("test.json","w",encoding="utf8"),ensure_ascii=False)