I have been implementing tests with the library and the need arose for me to have a function/method that closes the positions by "margin call" as in real brokers. So i added the following just previous to the native "next" method.

def check_margin_call(self,leverage,margin,entryprice,next_price,market):
    perc_var_leveraged = ((next_price-entryprice)/entryprice) * leverage
    if market=='bull' and \
        (perc_var_leveraged < 0) and \
        abs(perc_var_leveraged) >= margin:
        return True
    elif market=='bear' and \
        (perc_var_leveraged > 0) and \
        abs(perc_var_leveraged) >= margin:
        return True
    else:
        return False

def next(self):
    ...
    if self.position:
        if self.check_margin_call(leverage, margin, entryprice, next_price=close):
            self.log('POSITION CLOSED BY MARGIN CALL !!')
            self.close()        

I leave this code snippet here in case it helps someone.