toString method
A string representation of this object.
Some classes have a default textual representation,
often paired with a static parse function (like int.parse).
These classes will provide the textual representation as
their string representation.
Other classes have no meaningful textual representation
that a program will care about.
Such classes will typically override toString to provide
useful information when inspecting the object,
mainly for debugging or logging.
Implementation
@override
String toString() => '(placement: $placement, '
'instanceIdentity: $instanceIdentity, '
'name: $name, '
'variationId: $variationId, '
'_products: $_products, '
'_webPurchaseUrl: $_webPurchaseUrl)';