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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_crypt_class(self):
 """ Get the Keyczar class to use. The class can be customized with the ENCRYPTED_FIELD_MODE setting. By default, this setting is DECRYPT_AND_ENCRYPT. Set this to ENCRYPT to disable decryption. This is necessary if you are only providing public keys to Keyczar. Returns: keyczar.Encrypter if ENCRYPTED_FIELD_MODE is ENCRYPT. keyczar.Crypter if ENCRYPTED_FIELD_MODE is DECRYPT_AND_ENCRYPT. Override this method to customize the type of Keyczar class returned. """

        crypt_type = getattr(settings, 'ENCRYPTED_FIELD_MODE', 'DECRYPT_AND_ENCRYPT')
        if crypt_type == 'ENCRYPT':
            crypt_class_name = 'Encrypter'
        elif crypt_type == 'DECRYPT_AND_ENCRYPT':
            crypt_class_name = 'Crypter'
        else:
            raise ImproperlyConfigured(
                'ENCRYPTED_FIELD_MODE must be either DECRYPT_AND_ENCRYPT '
                'or ENCRYPT, not %s.' % crypt_type)
        return getattr(keyczar, crypt_class_name)