Same as ``find()`` but returns only the first result, or `None` if
        nothing was found.

def find_one(self, *args, **kwargs):
        """
        Same as ``find()`` but returns only the first result, or `None` if
        nothing was found.
        """
        try:
            return next(self.find(*args, **kwargs))
        except StopIteration:
            return None