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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_user(self, username):
 """ Given the verified username, look up and return the corresponding user account if it exists, or ``None`` if it doesn't. """

        User = get_user_model()  # noqa
        try:
            user = User.objects.get(**{
                User.USERNAME_FIELD: username,
                'is_active': False
            })
            return user
        except User.DoesNotExist:
            return None