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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 plot_state_histogram(self, ax):
 """ Visualize the complex matrix elements of the estimated state. :param matplotlib.Axes ax: A matplotlib Axes object to plot into. """

        title = "Estimated state"
        nqc = int(round(np.log2(self.rho_est.data.shape[0])))
        labels = ut.basis_labels(nqc)
        return ut.state_histogram(self.rho_est, ax, title)