Write the python code for the below requirement
there are n different models of mobiles manufactured at a mobile manufacturing unit. each mobile must go through 2 major phases: ‘parts manufacturing’ and ‘assembling’. obviously, ‘parts manufacturing’ must happen before "assembling’. the time for ‘parts manufacturing’ and ‘assembling’ (pmi and ai for ith mobile) for every mobile may be different. if we have only 1 unit for ‘parts manufacturing’ and 1 unit for ‘assembling’, how should we produce n mobiles in a suitable order such that the total production time is minimised