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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 _log_multivariate_normal_density_tied(X, means, covars):
 """Compute Gaussian log-density at X for a tied model."""

    cv = np.tile(covars, (means.shape[0], 1, 1))
    return _log_multivariate_normal_density_full(X, means, cv)