# Python Code Example: arithmetic functions on lists

In Python we can apply arithmetic functions to lists. The `mean()` method returns the arithmetic mean of data. The `median()` method also returns the mean of numeric data with additional information. The `stdev()` method returns the square root of the sample variance.

## Code Explanation

``````from statistics import mean, median, variance, stdev

myList = [1, 2, 3, 4, 5, 6, 7, 8]

# Return the sample arithmetic mean of data.
print(mean(myList))
# Return the median (middle value) of numeric data.
# When the number of data points is odd, return the middle data point.
# When the number of data points is even, the median is interpolated by taking the average of the two middle values
print(median(myList))
# Return the sample variance of data.
# data should be an iterable of Real-valued numbers, with at least two values.
# The optional argument xbar, if given, should be the mean of the data. If it is missing or None, the mean is automatically calculated.
print(variance(myList))
# Return the square root of the sample variance.
print(stdev(myList))``````
##### Output
``````4.5
4.5
6.0
2.449489742783178``````