def _float_validator(x, function):
    message = (function + ' must be a positive float')
    if ((x < 0) or (type(x) != float)):
        raise ValueError(message)
    return x
def _float_validator(x, function):
    message = (function + ' must be a positive float')
    if ((x < 0) or (type(x) != float)):
        raise ValueError(message)
    return x