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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 coincident_parameters(nodes1, nodes2):
 r"""Check if two B |eacute| zier curves are coincident. Does so by projecting each segment endpoint onto the other curve .. math:: B_1(s_0) = B_2(0) B_1(s_m) = B_2(1) B_1(0) = B_2(t_0) B_1(1) = B_2(t_n) and then finding the "shared interval" where both curves are defined. If such an interval can't be found (e.g. if one of the endpoints can't be located on the other curve), returns :data:`None`. If such a "shared interval" does exist, then this will specialize each curve onto that shared interval and check if the new control points agree. Args: nodes1 (numpy.ndarray):
 Set of control points for a B |eacute| zier curve. nodes2 (numpy.ndarray):
 Set of control points for a B |eacute| zier curve. Returns: parameters where the two coincident curves meet. If they are not coincident, returns :data:`None`. """

    # NOTE: There is no corresponding "enable", but the disable only applies
    #       in this lexical scope.
    # pylint: disable=too-many-return-statements,too-many-branches
    nodes1, nodes2 = make_same_degree(nodes1, nodes2)
    s_initial = _curve_helpers.locate_point(
        nodes1, nodes2[:, 0].reshape((2, 1), order="F")
    )
    s_final = _curve_helpers.locate_point(
        nodes1, nodes2[:, -1].reshape((2, 1), order="F")
    )
    if s_initial is not None and s_final is not None:
        # In this case, if the curves were coincident, then ``curve2``
        # would be "fully" contained in ``curve1``, so we specialize
        # ``curve1`` down to that interval to check.
        specialized1 = _curve_helpers.specialize_curve(
            nodes1, s_initial, s_final
        )
        if _helpers.vector_close(
            specialized1.ravel(order="F"), nodes2.ravel(order="F")
        ):
            return ((s_initial, 0.0), (s_final, 1.0))

        else:
            return None

    t_initial = _curve_helpers.locate_point(
        nodes2, nodes1[:, 0].reshape((2, 1), order="F")
    )
    t_final = _curve_helpers.locate_point(
        nodes2, nodes1[:, -1].reshape((2, 1), order="F")
    )
    if t_initial is None and t_final is None:
        # An overlap must have two endpoints and since at most one of the
        # endpoints of ``curve2`` lies on ``curve1`` (as indicated by at
        # least one of the ``s``-parameters being ``None``), we need (at least)
        # one endpoint of ``curve1`` on ``curve2``.
        return None

    if t_initial is not None and t_final is not None:
        # In this case, if the curves were coincident, then ``curve1``
        # would be "fully" contained in ``curve2``, so we specialize
        # ``curve2`` down to that interval to check.
        specialized2 = _curve_helpers.specialize_curve(
            nodes2, t_initial, t_final
        )
        if _helpers.vector_close(
            nodes1.ravel(order="F"), specialized2.ravel(order="F")
        ):
            return ((0.0, t_initial), (1.0, t_final))

        else:
            return None

    if s_initial is None and s_final is None:
        # An overlap must have two endpoints and since exactly one of the
        # endpoints of ``curve1`` lies on ``curve2`` (as indicated by exactly
        # one of the ``t``-parameters being ``None``), we need (at least)
        # one endpoint of ``curve1`` on ``curve2``.
        return None

    # At this point, we know exactly one of the ``s``-parameters and exactly
    # one of the ``t``-parameters is not ``None``.
    if s_initial is None:
        if t_initial is None:
            # B1(s_final) = B2(1) AND B1(1) = B2(t_final)
            start_s = s_final
            end_s = 1.0
            start_t = 1.0
            end_t = t_final
        else:
            # B1(0) = B2(t_initial) AND B1(s_final) = B2(1)
            start_s = 0.0
            end_s = s_final
            start_t = t_initial
            end_t = 1.0
    else:
        if t_initial is None:
            # B1(s_initial) = B2(0) AND B1(1 ) = B2(t_final)
            start_s = s_initial
            end_s = 1.0
            start_t = 0.0
            end_t = t_final
        else:
            # B1(0) = B2(t_initial) AND B1(s_initial) = B2(0)
            start_s = 0.0
            end_s = s_initial
            start_t = t_initial
            end_t = 0.0
    width_s = abs(start_s - end_s)
    width_t = abs(start_t - end_t)
    if width_s < _MIN_INTERVAL_WIDTH and width_t < _MIN_INTERVAL_WIDTH:
        return None

    specialized1 = _curve_helpers.specialize_curve(nodes1, start_s, end_s)
    specialized2 = _curve_helpers.specialize_curve(nodes2, start_t, end_t)
    if _helpers.vector_close(
        specialized1.ravel(order="F"), specialized2.ravel(order="F")
    ):
        return ((start_s, start_t), (end_s, end_t))

    else:
        return None