@staticmethod
def get_br_key_with_new_link(br_key, new_bit_pos, new_kind):
    """
        Say new_bit_pos=2 and new_kind=True. This returns a new branch key
        with '2T' added to the end of the string br_key

        Parameters
        ----------
        br_key : str
        new_bit_pos : int
        new_kind : bool

        Returns
        -------
        str

        """
    x = str(new_bit_pos) + ('T' if new_kind else 'F')
    if br_key == 'pure':
        new_br_key = x
    else:
        new_br_key = br_key + x
    return new_br_key
