def __init__(self, value_type, strict=True, default=set, **kwargs):
self.strict = strict<EOL>super(Set, self).__init__(value_type, default=default, **kwargs)<EOL>
:param value_type: a column class indicating the types of the value
:param strict: sets whether non set values will be coerced to set
    type on validation, or raise a validation error, defaults to True