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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 user_entry(entry_int, num_inst, command):
 """Validate user entry and returns index and validity flag. Processes the user entry and take the appropriate action: abort if '0' entered, set validity flag and index is valid entry, else return invalid index and the still unset validity flag. Args: entry_int (int):
 a number entered or 999 if a non-int was entered. num_inst (int):
 the largest valid number that can be entered. command (str):
 program command to display in prompt. Returns: entry_idx(int):
 the dictionary index number of the targeted instance valid_entry (bool):
 specifies if entry_idx is valid. Raises: SystemExit: if the user enters 0 when they are choosing from the list it triggers the "abort" option offered to the user. """

    valid_entry = False
    if not entry_int:
        print("{}aborting{} - {} instance\n".
              format(C_ERR, C_NORM, command))
        sys.exit()
    elif entry_int >= 1 and entry_int <= num_inst:
        entry_idx = entry_int - 1
        valid_entry = True
    else:
        print("{}Invalid entry:{} enter a number between 1"
              " and {}.".format(C_ERR, C_NORM, num_inst))
        entry_idx = entry_int
    return (entry_idx, valid_entry)