Dataframe commands can be used in order to find the basic statistical measures of columns or rows in a dataframe - for particular stocks
cl_price.mean() gives the mean close price of each of the stocks (each stock is a column, date is the row/index)
cl_price.std() gives the standard deviation price of each of the stocks
cl_price.describe() gives the basic data like mean median, std, min, max, percentile values for each stock
cl_price.head(<number>) displays the first n number of rows of the dataframe cl_price. tail does the same thing with the last rows