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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 minor_residues_per_turn(self, minor_repeat=None):
 """Calculates the number of residues per turn of the minor helix. Parameters minor_repeat : float, optional Hydrophobic repeat of the minor helix. Returns ------- minor_rpt : float Residues per turn of the minor helix. """

        if minor_repeat is None:
            minor_rpt = _helix_parameters[self.minor_helix_type][0]
        else:
            # precession angle in radians
            precession = self.curve.t_from_arc_length(
                minor_repeat * self.minor_rise_per_residue)
            if self.orientation == -1:
                precession = -precession
            if self.major_handedness != self.minor_handedness:
                precession = -precession
            minor_rpt = ((minor_repeat * numpy.pi * 2) /
                         ((2 * numpy.pi) + precession))
        return minor_rpt