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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 copy_configs(configs, source, target):
 """ Copy dynamips configs to converted topology :param configs: Configs to copy :param str source: Source topology directory :param str target: Target topology files directory :return: True when a config cannot be found, otherwise false :rtype: bool """

    config_err = False
    if len(configs) > 0:
        config_dir = os.path.join(target, 'dynamips', 'configs')
        os.makedirs(config_dir)
        for config in configs:
            old_config_file = os.path.join(source, config['old'])
            new_config_file = os.path.join(config_dir,
                                           os.path.basename(config['new']))
            if os.path.isfile(old_config_file):
                # Copy and rename the config
                shutil.copy(old_config_file, new_config_file)
            else:
                config_err = True
                logging.error('Unable to find %s' % config['old'])
    return config_err