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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 create_user(self, claims):
 """ Create the user if it doesn't exist yet Args: claims (dict):
 claims from the access token Returns: django.contrib.auth.models.User: A Django user """

        # Create the user
        username_claim = settings.USERNAME_CLAIM
        usermodel = get_user_model()
        user, created = usermodel.objects.get_or_create(**{
            usermodel.USERNAME_FIELD: claims[username_claim]
        })
        if created or not user.password:
            user.set_unusable_password()
            logger.debug("User '{}' has been created.".format(claims[username_claim]))

        return user