[Python] Why does 'input()' blocks Python thread?

I have this tiny code, that takes two functions and runs them asynchrounously. One function uses the input() method for receiving a value from standard input. The other function uses asyncio.sleep().

import asyncio

async def in_out():
for a in range(0, 3):
x = input("input value: ")
print(x)

async def chrono():
for a in range(0, 3):
await asyncio.sleep(1)
print(f"{a} seg.")


async def main():
L = await asyncio.gather(
chrono(),
in_out(),
)

asyncio.run(main())


When executed, the output is something like:

input value: a
a
input value: b
b
input value: c
c
0 seg.
1 seg.
2 seg.


My question is, why does the time for sleep, stops while the function input() is blocking the I/O, shouldn't the asyncio execute both functions concurrently?

Even if the I/O is blocked, I would expect something like:

input value: a
a
0 seg.
1 seg.
input value: b
2 seg.
b
input value: c
c


I am not asking how can I write a program that does that. That is not my issue. I just want to understand what is going on.

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