'Create a list of Attribute instances.
:param attrvals: A dictionary of attributes and values
:return: A list of Attribute instances'

def to_(self, attrvals):

    attributes = []
    for (key, value) in attrvals.items():
        key = key.lower()
        attributes.append(factory(saml.Attribute, name=key, name_format=self.name_format, attribute_value=do_ava(value)))
    return attributes
