(self, name)
return name in _ALL_FIELDS
return True if name is a valid metadata key
return True if name is a valid metadata key
return True if name is a valid metadata key
def is_field(self, name):
        """return True if name is a valid metadata key"""
        name = self._convert_name(name)
        return name in _ALL_FIELDS
def is_field ( self , name ) : name = self . _convert_name ( name ) return name in _ALL_FIELDS