The function _pre_process_did currently contains a typo in its parameter name on line 71. The parameter "nfirstperiod" should be replaced with "nfirst_period". This appears to be a simple typographical error that might have unintended consequences or cause confusion for users who interact with this function.
Steps to Reproduce:
Navigate to the file containing the _pre_process_did function.
Locate the function definition.
Examine the parameter list on line 71.
The function _pre_process_did currently contains a typo in its parameter name on line 71. The parameter "nfirstperiod" should be replaced with "nfirst_period". This appears to be a simple typographical error that might have unintended consequences or cause confusion for users who interact with this function.
Steps to Reproduce:
Navigate to the file containing the _pre_process_did function. Locate the function definition. Examine the parameter list on line 71.