Returns the requested SAML attribute.

        :param name: Name of the attribute
        :type name: string

        :returns: Attribute value if exists or []
        :rtype: string

def get_attribute(self, name):
        """
        Returns the requested SAML attribute.

        :param name: Name of the attribute
        :type name: string

        :returns: Attribute value if exists or []
        :rtype: string
        """
        assert isinstance(name, basestring)
        value = None
        if self.__attributes and name in self.__attributes.keys():
            value = self.__attributes[name]
        return value