convert for loop to dictionary comprehension

I'm trying to convert my for loop into dictionary comprehension but it seems to not work as dictionary comprehension can only change one key/value pair at a time.

def get_data(arr, target_time) ->pd.DataFrame:
   totalResult = pd.DataFrame()
   parameter = { "Period": "One Hour"}
   for value in arr:
      parameter.update(
         {
            "Test1": "dataset =$Prod$ metric_class=$ProcessPath$",
            "FunctionExpression": f"(AVG("value"))",
            "FunctionLabel": f"{value}_average_rate",
         }
      )
      phaseResult = get_data_from_database(parameter, target_time) ##internal function
      phaseResult = restructure_data(phaseResult, target_time, "mean", False) ## internal function
      totalResult = totalResult.append(phaseResult, sort=True)
   return totalResult