@staticmethod
def sta_get_tot_num_bits(parent_num_bits, gate_str_to_rads_list):
    """
        This static (sta) method returns the total number of qbits for the
        quantum circuit generated by this class, i.e., it returns the sum of
        the qbits used by each subcircuit.

        Parameters
        ----------
        parent_num_bits : int
        gate_str_to_rads_list : dict[str, list[float]]

        Returns
        -------
        int

        """
    num_subckts = len(gate_str_to_rads_list) * 2
    if 'prior' in gate_str_to_rads_list:
        num_subckts -= 1
    return num_subckts * (parent_num_bits + 1)
