input: Write a python function to calculate the average power consumption of all the households in the `householdList` given the consumption factors for various devices.
  ```python
  assert calculate_average_consumption(householdList) == expected_value
output: def calculate_average_consumption(householdList):
      total_consumption = 0
      total_households = len(householdList)
      
      for household in householdList:
          household_consumption = 0
          for device, factor in household.items():
              household_consumption += factor
          total_consumption += household_consumption
      
      if total_households == 0:
          return 0
  
      return total_consumption / total_households