def __imul__(self, coef):
        '''In-place multiplication by a scalar.'''
        if self.read_only:
            raise ReadOnlyException()
        if coef == 1:
            return self
        for name in self._counters():
            self[name] *= coef
        return self
def __imul__ ( self , coef ) : if self . read_only : raise ReadOnlyException ( ) if coef == 1 : return self for name in self . _counters ( ) : self [ name ] *= coef return self
In-place multiplication by a scalar.