class A:
    def __init__(self, txt: str):
        self.w: F = None
        self.p: D = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.z: C = None
        self.u: H = None
        self.w: D = None
        self.t: G = None
        self.x: E = None
        self.o: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.r: D = None
        self.z: B = None
        self.y: A = None
        self.q: B = None
        self.s: G = None
        self.v: E = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.r: F = None
        self.t: H = None
        self.z: H = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.t: H = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.s: C = None
        self.r: H = None
        self.t: D = None
        self.u: A = None
        self.v: C = None
        self.y: C = None
        self.q: H = None
        self.o: H = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.r: H = None
        self.y: B = None
        self.t: F = None
        self.v: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.o: E = None
        self.v: A = None
        self.txt = txt

c = A("c")
j = B("j")
d = C("d")
l = D("l")
n = E("n")
e = F("e")
i = G("i")
f = H("f")

c.w = e
c.p = l
j.z = d
j.u = f
j.w = l
j.t = i
j.x = n
j.o = n
d.r = l
d.z = j
d.q = j
d.y = c
d.s = i
d.v = n
l.r = e
l.t = f
l.z = f
n.t = f
e.s = d
e.v = d
e.y = d
e.r = f
e.q = f
e.o = f
e.t = l
e.u = c
i.r = f
i.v = f
i.y = j
i.t = e
f.o = n
f.v = c
assert i.y.t.y.u.v.w.q.v.txt == "
class A:
    def __init__(self, txt: str):
        self.w: F = None
        self.p: D = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.z: C = None
        self.u: H = None
        self.w: D = None
        self.t: G = None
        self.x: E = None
        self.o: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.r: D = None
        self.z: B = None
        self.y: A = None
        self.q: B = None
        self.s: G = None
        self.v: E = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.r: F = None
        self.t: H = None
        self.z: H = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.t: H = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.s: C = None
        self.r: H = None
        self.t: D = None
        self.u: A = None
        self.v: C = None
        self.y: C = None
        self.q: H = None
        self.o: H = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.r: H = None
        self.y: B = None
        self.t: F = None
        self.v: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.o: E = None
        self.v: A = None
        self.txt = txt

c = A("c")
j = B("j")
d = C("d")
l = D("l")
n = E("n")
e = F("e")
i = G("i")
f = H("f")

c.w = e
c.p = l
j.z = d
j.u = f
j.w = l
j.t = i
j.x = n
j.o = n
d.r = l
d.z = j
d.q = j
d.y = c
d.s = i
d.v = n
l.r = e
l.t = f
l.z = f
n.t = f
e.s = d
e.v = d
e.y = d
e.r = f
e.q = f
e.o = f
e.t = l
e.u = c
i.r = f
i.v = f
i.y = j
i.t = e
f.o = n
f.v = c
assert i.y.t.y.u.v.w.q.v.txt == "c"