code: def clean(s: TextSeries, pipeline=None) -> TextSeries:
      """
      Pre-process a text-based Pandas Series, by using the following default
      pipeline.
  
       Default pipeline:
       1. :meth:`texthero.preprocessing.fillna`
       2. :meth:`texthero.preprocessing.lowercase`
       3. :meth:`texthero.preprocessing.remove_digits`
       4. :meth:`texthero.preprocessing.remove_html_tags`
       5. :meth:`texthero.preprocessing.remove_punctuation`
       6. :meth:`texthero.preprocessing.remove_diacritics`
       7. :meth:`texthero.preprocessing.remove_stopwords`
       8. :meth:`texthero.preprocessing.remove_whitespace`
  
      Parameters
      ----------
      s : :class:`texthero._types.TextSeries`
  
      pipeline : List[Callable[Pandas Series, Pandas Series]],
                 optional, default=None
         Specific pipeline to clean the texts. Has to be a list
         of functions taking as input and returning as output
         a Pandas Series. If None, the default pipeline
         is used.
  
      Examples
      --------
      For the default pipeline:
  
      >>> import texthero as hero
      >>> import pandas as pd
      >>> s = pd.Series("Uper 9dig.        he her ÄÖÜ")
      >>> hero.clean(s)
      0    uper 9dig aou
      dtype: object
      """
  
      if not pipeline:
          pipeline = get_default_pipeline()
  
      for f in pipeline:
          s = s.pipe(f)
      return s
  
imports: from gensim.models.phrases import Phrases
  import re
  import string
  from typing import Optional, Set
  import unicodedata
  import numpy
  import pandas
  from texthero._types import TokenSeries, TextSeries, InputSeries
  from typing import List, Callable, Union
  import warnings
label_desc: Use image node_id 14 for calling a global function with example usage: clean(s, pipeline) and returns: s