'Initialises the BarEvent.
Parameters:
ticker - The ticker symbol, e.g. \'GOOG\'.
time - The timestamp of the bar
period - The time period covered by the bar in seconds
open_price - The unadjusted opening price of the bar
high_price - The unadjusted high price of the bar
low_price - The unadjusted low price of the bar
close_price - The unadjusted close price of the bar
volume - The volume of trading within the bar
adj_close_price - The vendor adjusted closing price
(e.g. back-adjustment) of the bar
Note: It is not advised to use \'open\', \'close\' instead
of \'open_price\', \'close_price\' as \'open\' is a reserved
word in Python.'

def __init__(self, ticker, time, period, open_price, high_price, low_price, close_price, volume, adj_close_price=None):

    self.type = EventType.BAR
    self.ticker = ticker
    self.time = time
    self.period = period
    self.open_price = open_price
    self.high_price = high_price
    self.low_price = low_price
    self.close_price = close_price
    self.volume = volume
    self.adj_close_price = adj_close_price
    self.period_readable = self._readable_period()
