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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, value):
 """Validate a value for this field. If the field is invalid, this will raise a ValueError. Runs ``pre_validate`` hook prior to validation, and returns value if validation passes."""

        value = self.pre_validate(value)
        if not self._typecheck(value):
            raise ValueError('%r failed type check' % value)
        return value