(fn, timeout=5.0, delay=0.1)
return v
Calls ``fn`` every ``delay`` seconds until it returns True or
    ``timeout`` seconds elapse. Returns True if the lock was acquired, or False
    if the timeout was reached.

    :param timeout: Length of time (in seconds) to keep retrying to acquire the
        lock. 0 means return immediately. Only used when blocking is False.
    :param delay: How often (in seconds) to retry acquiring the lock during
        the timeout period. Only used when blocking is False and timeout > 0.
Calls ``fn`` every ``delay`` seconds until it returns True or
    ``timeout`` seconds elapse. Returns True if the lock was acquired, or False
    if the timeout was reached.
Calls fn every delay seconds until it returns True or timeout seconds elapse . Returns True if the lock was acquired or False if the timeout was reached .
def try_for(fn, timeout=5.0, delay=0.1):
    """Calls ``fn`` every ``delay`` seconds until it returns True or
    ``timeout`` seconds elapse. Returns True if the lock was acquired, or False
    if the timeout was reached.

    :param timeout: Length of time (in seconds) to keep retrying to acquire the
        lock. 0 means return immediately. Only used when blocking is False.
    :param delay: How often (in seconds) to retry acquiring the lock during
        the timeout period. Only used when blocking is False and timeout > 0.
    """

    until = time.time() + timeout
    v = fn()
    while not v and time.time() < until:
        time.sleep(delay)
        v = fn()
    return v
def try_for ( fn , timeout = 5.0 , delay = 0.1 ) : until = time . time ( ) + timeout v = fn ( ) while not v and time . time ( ) < until : time . sleep ( delay ) v = fn ( ) return v