import sys

def lament(*args, **kwargs):
    print(*args, file=sys.stderr, **kwargs)

def lower_priority():
    """Set the priority of the process to below-normal."""
    # via https://stackoverflow.com/a/1023269
    if sys.platform == 'win32':
        try:
            import win32api, win32process, win32con
            pid = win32api.GetCurrentProcessId()
            handle = win32api.OpenProcess(win32con.PROCESS_ALL_ACCESS, True, pid)
            win32process.SetPriorityClass(handle, win32process.BELOW_NORMAL_PRIORITY_CLASS)
        except ImportError:
            lament("you do not have pywin32 installed.")
            lament("the process priority could not be lowered.")
            lament("consider: python -m pip install pypiwin32")
            lament("consider: conda install pywin32")
    else:
        import os
        os.nice(1)

# more

_log_was_update = False
def log(left, right, update=False):
    s = "\x1B[1m  {:>20}:\x1B[0m   {}".format(left, right)
    global _log_was_update
    if update and _log_was_update:
        lament('\x1B[F' + s)
    else:
        lament(s)
    _log_was_update = update

class Dummy:
    pass