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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 _covar_mstep_spherical(*args):
 """Performing the covariance M step for spherical cases"""

    cv = _covar_mstep_diag(*args)
    return np.tile(cv.mean(axis=1)[:, np.newaxis], (1, cv.shape[1]))