def update_row(engine, table_name, primary_key, column_to_update, new_value):
    """
    Performs an update of a row in the database.

    Inputs
    ------
    engine (sqlalchemy.engine.base.Engine): SQLAlchemy engine connected to a
        CockroachDB cluster.
    table_name (string): Name of the table you are updating
    primary_key (string): Representation of the UUID for id of the row.
    column_name (string): Name of the column you're working with.
    new_value (string): String representation of the new value you're adding
        to the row.

    """
    return engine.execute(("UPDATE {table} SET {column} = '{value}' "
                           "WHERE id = '{primary_key_value}'"
                           ).format(table=table_name, column=column_to_update,
                                    primary_key_value=primary_key,
                                    value=new_value))