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from collections import OrderedDict

from itertools import islice, takewhile

from typing import IO, Any, Iterator

def dumps(v: Any) -> str:

"""Bencodes any type of data into a string"""

if isinstance(v, int):

return f'i{v}e'

elif isinstance(v, str):

return f'{len(v)}:{v}'

elif isinstance(v, bytes):

return f'{len(v)}:{v.decode("utf8")}'

elif isinstance(v, list):

return f'l{"".join(dumps(i) for i in v)}e'

elif isinstance(v, dict | OrderedDict):

out = 'd'

for key, value in v.items():

key = dumps(key)

value = dumps(value)

out += f'{key}{value}'

return out + 'e'

def dump(data: Any, io: IO[bytes], encoding: str = 'utf8') -> None:

"""Bencodes data and writes the bytes result into the io"""

encoded = dumps(data).encode(encoding)

io.write(encoded)

def sdump(data: Any, io: IO[str]) -> None:

"""Bencodes data and writes the string result into the io"""

encoded = dumps(data)

io.write(encoded)

def loads(data: bytes) -> Any:

"""Unpacks bencoded data"""

it = iter(data)

return _loads(it)

def _loads(it: Iterator) -> Any:

ch = next(it)

if ch == 0x69: # 'i': int

digits = takewhile(lambda x: x != 0x65, it)

return int(bytes(digits))

elif 48 <= ch <= 57: # '0' < ch < '9': string | bytes

length = [ch, *takewhile(lambda x: x != 0x3a, it)]

length = int(''.join(chr(i) for i in length))

return bytes(islice(it, length))

elif ch == 0x6c: # 'l': list

arr = []

while True:

item = _loads(it)

if item is None:

break

arr.append(item)

return arr

elif ch == 0x64: # 'd': dictionary

odict = OrderedDict()

while True:

key = _loads(it)

if key is None:

break

value = _loads(it)

odict[key] = value

return odict

elif ch == 0x65: # 'e': end of the list or dict

return None

def load(io: IO[bytes]) -> Any:

"""Reads benocded data from the io"""

return loads(io.read())