code: def md_entry(node):
      
      key = None
      value = None
      if 'key' in node.attrib:
          key = node.attrib['key']
      else:
          key = None
  
      if key in ['time', 'elevation'] or key.startswith('custom_dimension'):
          value = md_dimension_info(key, node.find("dimensionInfo"))
      elif key == 'DynamicDefaultValues':
          value = md_dynamic_default_values_info(key, node.find("DynamicDefaultValues"))
      elif key == 'JDBC_VIRTUAL_TABLE':
          value = md_jdbc_virtual_table(key, node.find("virtualTable"))
      else:
          value = node.text
  
      if None in [key, value]:
          return None
      else:
          return (key, value)
docs: Extract metadata entries from an xml node