How can I use different logical operators ( != > < ) in conditions?

Hi. I am trying to implement conditional responses with different logical operators (operands) like this:

  - condition:
    - type: slot
      name: some_slot
      operand: lesser_than
      value: 5

Note the key ‘operand’. The idea is to trigger the condition if some_slot < 5. This is not supported yet by RASA therefore I am getting this error when executing rasa train:

Key ‘operand’ was not defined.

Worth to mention:

I am not using the RASA internal code to analyze the conditions. Instead, I have implemented a rule to handle the user’s message in a custom action class in which, I am retrieving all the responses for a given intention from the domain, and then I check the conditions in my own code to deliver the matching response.

How can I avoid the mention error or how can I contribute this feature?

Thank you