Why the log in buffer.py can't print??

[Huixxi]

class Buffer:
"""
The core expert-parallel (EP) communication buffers for Mixture of Experts (MoE) model, which supports:
- high-throughput intranode all-to-all (dispatch and combine, using NVLink)
- high-throughput internode all-to-all (dispatch and combine, using RDMA without AR)
- low-latency all-to-all (dispatch and combine, using RDMA, AR supported)

Attributes:
    num_sms: the SMs used in high-throughput kernels.
    rank: the local rank number.
    group_size: the number of ranks in the group.
    group: the communication group.
    num_nvl_bytes: the buffer size for intranode NVLink communication.
    num_rdma_bytes: the buffer size for internode (also for intranode with low-latency mode) RDMA communication.
    runtime: the C++ runtime.
"""

num_sms: int = 20

def __init__(self, group: dist.ProcessGroup,
             num_nvl_bytes: int = 0, num_rdma_bytes: int = 0,
             low_latency_mode: bool = False, num_qps_per_rank: int = 1) -> None:
    """
    Initialize the communication buffer.

    Arguments:
        group: the communication group.
        num_nvl_bytes: the buffer size for intranode NVLink communication.
        num_rdma_bytes: the buffer size for internode (also for intranode with low-latency mode) RDMA communication.
        low_latency_mode: whether to enable low-latency mode.
        num_qps_per_rank: the number of QPs for RDMA, the low-latency mode requires that this number equals
            to the number of local experts.
    """

    # Initialize the CPP runtime
    print("=============================================", flush=True)
    self.rank = group.rank()
    self.group_size = group.size()
    self.group = group