"Expected type 'Union[str, bytearray]' got 'int' instead" warning in write method

Question

My script writes to file chunk by chunk, using pre-generated data patterns:

#  Data pattern generator    
def get_random_chunk_pattern():
            return ''.join(random.choice(ascii_uppercase + digits + ascii_lowercase) for _ in range(8))

....

# DedupChunk class CTOR:
class DedupChunk:
    def __init__(self, chunk_size, chunk_pattern, chunk_position=0, state=DedupChunkStates.PENDING):
        self._chunk_size = chunk_size  # chunk size in bytes
        self._chunk_pattern = chunk_pattern
        self._chunk_position = chunk_position
        self._state = state
        self.mapping = None

    @property
    def size(self):
        return self._chunk_size

    @property
    def pattern(self):
        return self._chunk_pattern

    @property
    def position(self):
        return self._chunk_position

    @property
    def state(self):
        return self._state

....

# Here Chunk object is being initialized (inside other class's CTOR):
chunk_size = random.randint(64, 192) * 1024  # in bytes
        while (position + chunk_size) < self.file_size:  # generating random chunks number
            self.chunks.append(DedupChunk(chunk_size, DedupChunkPattern.get_random_chunk_pattern(), position))

....

# Actual writing
    with open(self.path, 'rb+') as f:
        for chunk in self.chunks:
            f.write(chunk.pattern * (chunk.size // 8))

PyCharm displays "Expected type 'Union[str, bytearray]' got 'int' instead" warning in write method

But when removing the division in f.write(chunk.pattern * chunk.size), or doing division outside:

chunk.size //= 8
f.write(chunk.pattern * chunk.size)

warning disappeared

What actually happened here?

Thanks

Answer 1

To ignore the warning inline, add this comment above the line causing the warning

# noinspection PyTypeChecker