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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 check_theta(self):
 """Validate the computed theta against the copula specification. This method is used to assert the computed theta is in the valid range for the copula."""

        lower, upper = self.theta_interval
        if (not lower <= self.theta <= upper) or (self.theta in self.invalid_thetas):
            message = 'The computed theta value {} is out of limits for the given {} copula.'
            raise ValueError(message.format(self.theta, self.copula_type.name))