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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 is_modified(row, dialect):
 """ Has the row data been modified? This method inspects the row, and iterates over all columns looking for changes to the (processed) data, skipping over unmodified columns. :param row: SQLAlchemy model instance :param dialect: :py:class:`~sqlalchemy.engine.interfaces.Dialect` :return: True if any columns were modified, else False """

    ins = inspect(row)
    modified_cols = set(get_column_keys(ins.mapper)) - ins.unmodified
    for col_name in modified_cols:
        current_value = get_column_attribute(row, col_name, dialect=dialect)
        previous_value = get_column_attribute(row, col_name, use_dirty=False, dialect=dialect)
        if previous_value != current_value:
            return True
    return False