def validate(self, value):
        value = super(BaseFloat, self).validate(value)
        if value is None:
            return
        try:
            return float(value)
        except (__HOLE__, ValueError):
            raise ValidationError("{0} {1} is not a valid float".format(self.column_name, value))
dataset/ETHPy150Open datastax/python-driver/cassandra/cqlengine/columns.py/BaseFloat.validate