import math


def se_to_sd(serror, size):
    """
    Converts Standard Error to Standard deviation.
    Parameters:
        serror (float, required): The standard error of the data to be
            generated.
        size (float, required): The size of the population.
    Returns:
        float: A float value for the standard deviation.
    """
    sdev = serror*math.sqrt(size)
    return sdev