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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def validate(self):
 """ Error check model params. :raises TypeError: Throws TypeError if validation fails. """

        if self.nregions is None:
            raise TypeError("neutral regions cannot be None")
        if self.sregions is None:
            raise TypeError("selected regions cannot be None")
        if self.recregions is None:
            raise TypeError("recombination regions cannot be None")
        if self.demography is None:
            raise TypeError("demography cannot be None")
        if self.prune_selected is None:
            raise TypeError("prune_selected cannot be None")
        if self.gvalue is None:
            raise TypeError("gvalue cannot be None")
        if self.rates is None:
            raise TypeError("rates cannot be None")