def to_xml_string(str = '')
      str << '<tableStyles '
      serialized_attributes str, {:count => self.size }
      str << '>'
      each { |table_style| table_style.to_xml_string(str) }
      str << '</tableStyles>'
    end
def to_xml_string(str = '')
      str << '<tableStyles '
      serialized_attributes str, {:count => self.size }
      str << '>'
      each { |table_style| table_style.to_xml_string(str) }
      str << '</tableStyles>'
    end
Serializes the object
 @param [String] str
 @return [String]