class_docstr: Parallelly transforms input by common abbreviations in TwitterType.
  
  :param str mode: Twitter type, only support ['at', 'url', 'random']
class_docstr_tok: ["Parallelly","transforms","input","by","common","abbreviations","in","TwitterType",".",":","param","str","mode",":","Twitter","type",",","only","support","[","'at","'",",","'url","'",",","'random","'","]"]
code: def random_string(n):
      return "".join(
          np.random.choice(
              [x for x in string.ascii_letters + string.digits], n
          )
      )
  
file_path: textflint/textflint/generation/transformation/NMT/parallel_twitter_type.py
imports: import random
  import string
  import numpy
  from ....common.utils.error import FlintError
  from ....common.utils import logger
  from ..UT.twitter_type import TwitterType
label_desc: Use image node_id 6 for calling the ParallelTwitterType obj's underlying member method code with example usage: obj.random_string(n) and returns: str