docs: def checkUpload(self, file_obj, full_path = '/', overwrite = False):
          """Check whether it is possible to upload a file.
  
              >>> s = nd.checkUpload('~/flower.png','/Picture/flower.png')
  
          :param file_obj: A file-like object to check whether possible to upload. You can pass a string as a file_obj or a real file object.
          :param str full_path: The full path to upload the file to, *including the file name*. If the destination directory does not yet exist, it will be created. 
          :param overwrite: Whether to overwrite an existing file at the given path. (Default ``False``.)
              
          :return: ``True`` if possible to upload or ``False`` if impossible to upload.
          """
          try:
              file_obj = file_obj.name
          except:
              file_obj = file_obj # do nothing
  
          file_size = os.stat(file_obj).st_size
          now = datetime.datetime.now().isoformat()
  
          data = {'uploadsize': file_size,
                  'overwrite': 'T' if overwrite else 'F',
                  'getlastmodified': now,
                  'dstresource': full_path,
                  'userid': self.user_id,
                  'useridx': self.useridx,
                  }
  
          s, metadata = self.POST('checkUpload', data)
  
          if not s:
              print metadata
  
          return s