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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 get_local_extrema(self, find_min=True, threshold_frac=None, threshold_abs=None):
 """ Get all local extrema fractional coordinates in charge density, searching for local minimum by default. Note that sites are NOT grouped symmetrically. Args: find_min (bool):
 True to find local minimum else maximum, otherwise find local maximum. threshold_frac (float):
 optional fraction of extrema shown, which returns `threshold_frac * tot_num_extrema` extrema fractional coordinates based on highest/lowest intensity. E.g. set 0.2 to show the extrema with 20% highest or lowest intensity. Value range: 0 <= threshold_frac <= 1 Note that threshold_abs and threshold_frac should not set in the same time. threshold_abs (float):
 optional filter. When searching for local minima, intensity <= threshold_abs returns; when searching for local maxima, intensity >= threshold_abs returns. Note that threshold_abs and threshold_frac should not set in the same time. Returns: extrema_coords (list):
 list of fractional coordinates corresponding to local extrema. """

        sign, extrema_type = 1, "local maxima"

        if find_min:
            sign, extrema_type = -1, "local minima"

        # Make 3x3x3 supercell
        # This is a trick to resolve the periodical boundary issue.
        total_chg = sign * self.chgcar.data["total"]
        total_chg = np.tile(total_chg, reps=(3, 3, 3))
        coordinates = peak_local_max(total_chg, min_distance=1)

        # Remove duplicated sites introduced by supercell.
        f_coords = [coord / total_chg.shape * 3 for coord in coordinates]
        f_coords = [f - 1 for f in f_coords if
                    all(np.array(f) < 2) and all(np.array(f) >= 1)]

        # Update information
        self._update_extrema(f_coords, extrema_type,
                             threshold_frac=threshold_frac,
                             threshold_abs=threshold_abs)

        return self.extrema_coords