class A:
    def __init__(self, txt: str):
        self.s: F = None
        self.x: E = None
        self.v: B = None
        self.y: D = None
        self.z: D = None
        self.w: F = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.x: D = None
        self.w: F = None
        self.q: D = None
        self.r: C = None
        self.p: E = None
        self.u: A = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.w: A = None
        self.z: A = None
        self.s: D = None
        self.x: A = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.s: E = None
        self.z: F = None
        self.x: B = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.t: A = None
        self.r: B = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.p: A = None
        self.y: E = None
        self.o: A = None
        self.txt = txt

c = A("c")
l = B("l")
e = C("e")
b = D("b")
m = E("m")
i = F("i")
h = C("h")

c.s = i
c.w = i
c.x = m
c.v = l
c.y = b
c.z = b
l.x = b
l.q = b
l.w = i
l.r = e
l.p = m
l.u = c
e.w = c
e.z = c
e.x = c
e.s = b
b.s = m
b.z = i
b.x = l
m.t = c
m.r = l
i.p = c
i.o = c
i.y = m
h.w = c
h.z = c
h.x = c
h.s = b
assert l.u.y.s.t.x.txt == "
class A:
    def __init__(self, txt: str):
        self.s: F = None
        self.x: E = None
        self.v: B = None
        self.y: D = None
        self.z: D = None
        self.w: F = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.x: D = None
        self.w: F = None
        self.q: D = None
        self.r: C = None
        self.p: E = None
        self.u: A = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.w: A = None
        self.z: A = None
        self.s: D = None
        self.x: A = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.s: E = None
        self.z: F = None
        self.x: B = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.t: A = None
        self.r: B = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.p: A = None
        self.y: E = None
        self.o: A = None
        self.txt = txt

c = A("c")
l = B("l")
e = C("e")
b = D("b")
m = E("m")
i = F("i")
h = C("h")

c.s = i
c.w = i
c.x = m
c.v = l
c.y = b
c.z = b
l.x = b
l.q = b
l.w = i
l.r = e
l.p = m
l.u = c
e.w = c
e.z = c
e.x = c
e.s = b
b.s = m
b.z = i
b.x = l
m.t = c
m.r = l
i.p = c
i.o = c
i.y = m
h.w = c
h.z = c
h.x = c
h.s = b
assert l.u.y.s.t.x.txt == "m"