def check_for_period_error(data, period):
period = int(period)<EOL>data_len = len(data)<EOL>if data_len < period:<EOL><INDENT>raise Exception("<STR_LIT>")<EOL><DEDENT>
Check for Period Error.

This method checks if the developer is trying to enter a period that is
larger than the data set being entered. If that is the case an exception is
raised with a custom message that informs the developer that their period
is greater than the data set.