docs: def strip_namespaces(file_or_xml):
      """
      Removes all namespaces from the XML file or string passed in.
      If file_or_xml is not a file or string, it is returned as is.
      """
  
      xml_content = _xml_content_to_string(file_or_xml)
      if not isinstance(xml_content, string_types):
          return xml_content
  
      # This pattern can have overlapping matches, necessitating the loop
      while _NAMESPACES_FROM_DEC_REGEX.search(xml_content) is not None:
          xml_content = _NAMESPACES_FROM_DEC_REGEX.sub(r'\1', xml_content)
  
      # Remove namespaces at the tag level
      xml_content = _NAMESPACES_FROM_TAG_REGEX.sub(r'\1', xml_content)
  
      # Remove namespaces at the attribute level
      xml_content = _NAMESPACES_FROM_ATTR_REGEX.sub(r'\1\3', xml_content)
  
      return xml_content