text: # Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserved.
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #     http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  # number expansion is not that easy
  import re
  
  import inflect
  
  _inflect = inflect.engine()
  _comma_number_re = re.compile(r'([0-9][0-9\,]+[0-9])')
  _decimal_number_re = re.compile(r'([0-9]+\.[0-9]+)')
  _pounds_re = re.compile(r'£([0-9\,]*[0-9]+)')
  _dollars_re = re.compile(r'\$([0-9\.\,]*[0-9]+)')
  _ordinal_re = re.compile(r'[0-9]+(st|nd|rd|th)')
  _number_re = re.compile(r'[0-9]+')
  
  
  def _remove_commas(m):
      return m.group(1).replace(',', '')
  
  
  def _expand_decimal_point(m):
      return m.group(1).replace('.', ' point ')
  
  
  def _expand_dollars(m):
      match = m.group(1)
      parts = match.split('.')
      if len(parts) > 2:
          return match + ' dollars'  # Unexpected format
      dollars = int(parts[0]) if parts[0] else 0
      cents = int(parts[1]) if len(parts) > 1 and parts[1] else 0
      if dollars and cents:
          dollar_unit = 'dollar' if dollars == 1 else 'dollars'
          cent_unit = 'cent' if cents == 1 else 'cents'
          return '%s %s, %s %s' % (dollars, dollar_unit, cents, cent_unit)
      elif dollars:
          dollar_unit = 'dollar' if dollars == 1 else 'dollars'
          return '%s %s' % (dollars, dollar_unit)
      elif cents:
          cent_unit = 'cent' if cents == 1 else 'cents'
          return '%s %s' % (cents, cent_unit)
      else:
          return 'zero dollars'
  
  
  def _expand_ordinal(m):
      return _inflect.number_to_words(m.group(0))
  
  
  def _expand_number(m):
      num = int(m.group(0))
      if num > 1000 and num < 3000:
          if num == 2000:
              return 'two thousand'
          elif num > 2000 and num < 2010:
              return 'two thousand ' + _inflect.number_to_words(num % 100)
          elif num % 100 == 0:
              return _inflect.number_to_words(num // 100) + ' hundred'
          else:
              return _inflect.number_to_words(
                  num, andword='', zero='oh', group=2).replace(', ', ' ')
      else:
          return _inflect.number_to_words(num, andword='')
  
  
  def normalize_numbers(text):
      """ Normalize numbers in English text.
      """
      text = re.sub(_comma_number_re, _remove_commas, text)
      text = re.sub(_pounds_re, r'\1 pounds', text)
      text = re.sub(_dollars_re, _expand_dollars, text)
      text = re.sub(_decimal_number_re, _expand_decimal_point, text)
      text = re.sub(_ordinal_re, _expand_ordinal, text)
      text = re.sub(_number_re, _expand_number, text)
      return text
  