Conpot S7 Simulation Fails to Respond Properly to nmap s7-info.nse Script Scan

[ringringboy]

environment:ubuntu18.04 + python3.6 + conpot latest
scan tool：Nmap 7.94 
CMD：nmap -p 102 -d --script s7-info.nse <ip>

issue description: Using the Nmap tool s7-info.nse script to scan port 102 of the conpot, the PLC fingerprint cannot be identified. Is it because the conpot does not implement this function or there is a problem with my deployment?

the nmap error log is following:

Initiating NSE at 13:07
NSE: Starting s7-info against 192.168.153.134:102.
NSE: s7-info against 192.168.153.134:102 threw an error!
D:\Nmap/scripts\s7-info.nse:265: attempt to get length of a nil value (local 'output')
stack traceback:
    D:\Nmap/scripts\s7-info.nse:265: in function <D:\Nmap/scripts\s7-info.nse:190>
    (...tail calls...)

Completed NSE at 13:07, 5.02s elapsed

[ringringboy]

step1: gedit S7.py

We can replace S7.py, file from below:
s7comm file from https://github.com/Nootropico/conpot/blob/master/conpot/protocols/s7comm/s7.py

step2: gedit s7comm.xml

<ssl id="W#16#xy11" name="Module Identification">
            <!-- Not really sure what these are supposed to contain -->
            <module_identification id="W#16#0001">module</module_identification>
            <hardware_identification id="W#16#0006">hardware</hardware_identification>
            <firmware_identification id="W#16#0007">firmware</firmware_identification>
</ssl>

step3: gedit template.xml

<key name="module">
       <value type="value">"6eS7 212-1BD30-xXB0"</value>
</key>

<key name="hardware">
      <value type="value">"6eS7 212-1BD30-xXB0"</value>
</key>

<key name="firmware">
      <value type="value">"3.2.6"</value>
</key>

finally, nmap --script s7-info.nse work!!!

PORT    STATE SERVICE
102/tcp open  iso-tsap
| s7-info: 
|   Module: IM151-8 PN/DP CPU   
|   Basic Hardware: V3.22.7             
|   Version: 3.22.7
|   System Name: Technodrome
|   Module Type: IM151-8 PN/DP CPU
|   Serial Number: 88111222
|   Plant Identification: Mouser Factory
|_  Copyright: Original Siemens Equipment
MAC Address: 00:0C:29:6D:90:29 (VMware)
Service Info: Device: specialized