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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 run(self):
 """Run migrations in 'online' mode. In this scenario we need to create an Engine and associate a connection with the context. """

        connectable = engine_from_config(
            self._config.get_section(self._config.config_ini_section),
            prefix='sqlalchemy.',
            poolclass=pool.NullPool)

        with connectable.connect() as connection:
            ensureSchemaExists(connectable, self._schemaName)

            context.configure(
                connection=connection,
                target_metadata=self._targetMetadata,
                include_object=self._includeObjectFilter,
                include_schemas=True,
                version_table_schema=self._schemaName
            )

            with context.begin_transaction():
                context.run_migrations()