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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 _construct_X(self, omega, weighted=True, **kwargs):
 """Construct the design matrix for the problem"""

        t = kwargs.get('t', self.t)
        dy = kwargs.get('dy', self.dy)
        fit_offset = kwargs.get('fit_offset', self.fit_offset)

        if fit_offset:
            offsets = [np.ones(len(t))]
        else:
            offsets = []

        cols = sum(([np.sin((i + 1) * omega * t),
                     np.cos((i + 1) * omega * t)]
                    for i in range(self.Nterms)), offsets)

        if weighted:
            return np.transpose(np.vstack(cols) / dy)
        else:
            return np.transpose(np.vstack(cols))