code: def get_dev_and_path(filename):
      
      if DEFAULT_DEV:
          if DEFAULT_DEV.is_root_path(filename):
              return (DEFAULT_DEV, filename)
      test_filename = filename + '/'
      with DEV_LOCK:
          for dev in DEVS:
              if test_filename.startswith(dev.name_path):
                  dev_filename = filename[len(dev.name_path)-1:]
                  if dev_filename == '':
                      dev_filename = '/'
                  return (dev, dev_filename)
      return (None, filename)
docs: Determines if a given file is located locally or remotely. We assume
         that any directories from the pyboard take precedence over local
         directories of the same name. /flash and /sdcard are associated with
         the default device. /dev_name/path where dev_name is the name of a
         given device is also considered to be associated with the named device.
  
         If the file is associated with a remote device, then this function
         returns a tuple (dev, dev_filename) where dev is the device and
         dev_filename is the portion of the filename relative to the device.
  
         If the file is not associated with the remote device, then the dev
         portion of the returned tuple will be None.