code: def regex_replace(txt, rgx, val, ignorecase=False, multiline=False):
      r'''
      Searches for a pattern and replaces with a sequence of characters.
  
      .. code-block:: jinja
  
          {% set my_text = 'lets replace spaces' %}
          {{ my_text | regex_replace('\s+', '__') }}
  
      will be rendered as:
  
      .. code-block:: text
  
          lets__replace__spaces
      '''
      flag = 0
      if ignorecase:
          flag |= re.I
      if multiline:
          flag |= re.M
      compiled_rgx = re.compile(rgx, flag)
      return compiled_rgx.sub(val, txtf regex_replace(txt, rgx, val, ignorecase=False, multiline=False):
      r'''
      Searches for a pattern and replaces with a sequence of characters.
  
      .. code-block:: jinja
  
          {% set my_text = 'lets replace spaces' %}
          {{ my_text | regex_replace('\s+', '__') }}
  
      will be rendered as:
  
      .. code-block:: text
  
          lets__replace__spaces
      '''
      flag = 0
      if ignorecase:
          flag |= re.I
      if multiline:
          flag |= re.M
      compiled_rgx = re.compile(rgx, flag)
      return compiled_rgx.sub(val, txt)
docs: r'''
      Searches for a pattern and replaces with a sequence of characters.
  
      .. code-block:: jinja
  
          {% set my_text = 'lets replace spaces' %}
          {{ my_text | regex_replace('\s+', '__') }}
  
      will be rendered as:
  
      .. code-block:: text
  
          lets__replace__spaces