def validate_neighbor_entry_exist(duthost, neighbor_addr):
    """Validate if neighbor entry exist on duthost

    Args:
        duthost (AnsibleHost): Device Under Test (DUT)
        neighbor_addr (str): neighbor's ip address 

    Returns:
        bool: True if neighbor exists. Otherwise, return False.
    """
    command = "ip neighbor show %s" % neighbor_addr
    output = [_.strip() for _ in duthost.shell(command)["stdout_lines"]]
    if not output or "REACHABLE" not in output[0]:
        return False
    return True