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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 determine_inst(i_info, param_str, command):
 """Determine the instance-id of the target instance. Inspect the number of instance-ids collected and take the appropriate action: exit if no ids, return if single id, and call user_picklist function if multiple ids exist. Args: i_info (dict):
 information and details for instances. param_str (str):
 the title to display in the listing. command (str):
 command specified on the command line. Returns: tar_inst (str):
 the AWS instance-id of the target. Raises: SystemExit: if no instances are match parameters specified. """

    qty_instances = len(i_info)
    if not qty_instances:
        print("No instances found with parameters: {}".format(param_str))
        sys.exit(1)

    if qty_instances > 1:
        print("{} instances match these parameters:".format(qty_instances))
        tar_idx = user_picklist(i_info, command)

    else:
        tar_idx = 0
    tar_inst = i_info[tar_idx]['id']
    print("{0}{3}ing{1} instance id {2}{4}{1}".
          format(C_STAT[command], C_NORM, C_TI, command, tar_inst))
    return (tar_inst, tar_idx)