С чем может быть связана такая ошибка?
The await operator suspends evaluation of the enclosing async method until the asynchronous operation represented by its operand completes.
from threading import *
def work(i):
for _ in range(100):
print(f"hello i'm a thread #{i}")
t1 = Thread(target=work, args=(1,))
t2 = Thread(target=work, args=(2,))
t1.start()
t2.start()
t1.join()
t2.join()from threading import *
lock = Lock()
def work(i):
for _ in range(100):
with lock:
print(f"hello i'm a thread #{i}")
t1 = Thread(target=work, args=(1,))
t2 = Thread(target=work, args=(2,))
t1.start()
t2.start()
t1.join()
t2.join()from threading import *
from time import sleep
class GlobalState:
def __init__(self, x):
self.x = x
def set_x(self, x):
self.x = x
def reader(state: GlobalState):
if state.x % 2 == 0:
sleep(0.01) # simulate OS context switch
print(f"{state.x=} is even")
else:
print(f"{state.x=} is odd")
def changer(state: GlobalState):
state.set_x(state.x + 1)
state = GlobalState(2)
t1 = Thread(target=reader, args=(state,))
t2 = Thread(target=changer, args=(state,))
t1.start()
t2.start()
t1.join()
t2.join()from threading import *
from time import sleep
class GlobalState:
def __init__(self, x):
self.x = x
self.lock = Lock()
def set_x(self, x):
self.x = x
def reader(state: GlobalState):
with state.lock:
if state.x % 2 == 0:
sleep(0.01) # simulate OS context switch
print(f"{state.x=} is even")
else:
print(f"{state.x=} is odd")
def changer(state: GlobalState):
with state.lock:
state.set_x(state.x + 1)
state = GlobalState(2)
t1 = Thread(target=reader, args=(state,))
t2 = Thread(target=changer, args=(state,))
t1.start()
t2.start()
t1.join()
t2.join()from threading import *
from random import *
class GlobalState:
def __init__(self):
self.x = []
def do_something_changing(self):
if random() < 0.5:
self.x.append(1)
elif self.x:
self.x.pop()
def reader(state: GlobalState):
for _ in range(10000000):
if len(state.x) % 2 == 0:
if len(state.x) % 2 != 0: # wtf how it's possible?
print(f"length {len(state.x)} was even before context switch")
def changer(state: GlobalState):
for _ in range(10000000):
state.do_something_changing()
state = GlobalState()
t1 = Thread(target=reader, args=(state,))
t2 = Thread(target=changer, args=(state,))
t1.start()
t2.start()
t1.join()
t2.join()def filter_by(self, data: list, param: dict) -> list:
result = []
for el in data:
matches = True
for name, val in param.items():
if el[name] != val:
matches = False
break
if matches:
result.append(el)
return resultdef filter_by(self, data: list, param: dict) -> list:
return [el for el in data if all(el[name] == val for name, val in param.items())]