def STD_DEV_POP(*expression):
return {'<STR_LIT>': expression} if len(expression) > <NUM_LIT:1> else {'<STR_LIT>': expression[<NUM_LIT:0>]} if expression else {}<EOL>
Calculates the population standard deviation of the input values.
Use if the values encompass the entire population of data you want to represent
and do not wish to generalize about a larger population.
See https://docs.mongodb.com/manual/reference/operator/aggregation/stdDevPop/
for more details
:param expression: expression/expressions
:return: Aggregation operator