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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 sync_role_definitions(self):
 """Inits the Superset application with security roles and such"""

        from superset import conf
        logging.info('Syncing role definition')

        self.create_custom_permissions()

        # Creating default roles
        self.set_role('Admin', self.is_admin_pvm)
        self.set_role('Alpha', self.is_alpha_pvm)
        self.set_role('Gamma', self.is_gamma_pvm)
        self.set_role('granter', self.is_granter_pvm)
        self.set_role('sql_lab', self.is_sql_lab_pvm)

        if conf.get('PUBLIC_ROLE_LIKE_GAMMA', False):
            self.set_role('Public', self.is_gamma_pvm)

        self.create_missing_perms()

        # commit role and view menu updates
        self.get_session.commit()
        self.clean_perms()