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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_username(self, claims):
 """Generate username based on claims."""

        # bluntly stolen from django-browserid
        # https://github.com/mozilla/django-browserid/blob/master/django_browserid/auth.py
        username_algo = self.get_settings('OIDC_USERNAME_ALGO', None)

        if username_algo:
            if isinstance(username_algo, six.string_types):
                username_algo = import_string(username_algo)
            return username_algo(claims.get('email'))

        return default_username_algo(claims.get('email'))