'Instantiate a FeaturesBitField of size `size`. Optional parameter
`values` allows you to override the initial list of integers used to
store the values.'

def __init__(self, size, values=None):

    self.size = size
    if (values is not None):
        self.values = values
    else:
        self.values = ([0] * int(math.ceil((self.size / 8.0))))
