text: '''
  Legacy Em Extension for Python-Markdown
  =======================================
  
  This extention provides legacy behavior for _connected_words_.
  
  Copyright 2015-2018 The Python Markdown Project
  
  License: [BSD](https://opensource.org/licenses/bsd-license.php)
  
  '''
  
  from __future__ import absolute_import
  from __future__ import unicode_literals
  from . import Extension
  from ..inlinepatterns import SimpleTagInlineProcessor
  
  EMPHASIS_RE = r'(\*|_)(.+?)\1'
  STRONG_RE = r'(\*{2}|_{2})(.+?)\1'
  
  
  class LegacyEmExtension(Extension):
      """ Add legacy_em extension to Markdown class."""
  
      def extendMarkdown(self, md):
          """ Modify inline patterns. """
          md.inlinePatterns.register(SimpleTagInlineProcessor(STRONG_RE, 'strong'), 'strong', 40)
          md.inlinePatterns.register(SimpleTagInlineProcessor(EMPHASIS_RE, 'em'), 'emphasis', 30)
          md.inlinePatterns.deregister('strong2')
          md.inlinePatterns.deregister('emphasis2')
  