Bind field to its name in model class.

def bind_name(self, name):
        """Bind field to its name in model class."""
        if self.name:
            raise errors.Error('Already bound "{0}" with name "{1}" could not '
                               'be rebound'.format(self, self.name))
        self.name = name
        self.storage_name = ''.join(('_', self.name))
        return self