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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 cmd_list(options):
 """Gather data for instances matching args and call display func. Args: options (object):
 contains args and data from parser. """

    (i_info, param_str) = gather_data(options)
    if i_info:
        awsc.get_all_aminames(i_info)
        param_str = "Instance List - " + param_str + "\n"
        list_instances(i_info, param_str)
    else:
        print("No instances found with parameters: {}".format(param_str))