def __init__(self, field):
        """
        :param field: a single field with which to marshal the output.
        """
        if isinstance(field, type):
            self.field = field()
        else:
            self.field = field
def __init__ ( self , field ) : if isinstance ( field , type ) : self . field = field ( ) else : self . field = field
:param field: a single field with which to marshal the output.