input: Write a python function to check disk usage and return a status message.
  assert check_df("/", 85, 95, ["/var/lib"])[1] in [0, 1, 2, 3]
  assert isinstance(check_df("/", 85, 95, ["/var/lib"])[0], str)
  assert check_df("/mnt", 80, 90, ["/mnt/temp"])[1] in [0, 1, 2, 3]
output: import shutil
  import os
  
  def check_df(mount_point, warning_threshold, critical_threshold, exclude_paths):
      total, used, free = shutil.disk_usage(mount_point)
      percent_used = (used / total) * 100
  
      if any(os.path.commonpath([mount_point, exclude]) == mount_point for exclude in exclude_paths):
          return "Excluded paths present", 3
  
      if percent_used >= critical_threshold:
          return "Critical: Disk usage exceeded critical threshold", 2
      elif percent_used >= warning_threshold:
          return "Warning: Disk usage exceeded warning threshold", 1
      else:
          return "OK: Disk usage is within acceptable limits", 0