The Datatype class must provide some object representation of the type that the validator can use for equality comparison and hash code calculation.

datatype类必须提供类型的某种对象表示，以便验证器可用来进行相等性比较和计算散列码。

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Its ultimate aim is independence, which it believes, will mean "direct representation and equality of status in Europe", with Scotland becoming a full member state.

BBC: SNP pledge to be 'Scotland's voice'