class A:
    def __init__(self, txt: str):
        self.u: F = None
        self.y: C = None
        self.z: B = None
        self.v: E = None
        self.t: D = None
        self.txt = txt

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

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

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

class E:
    def __init__(self, txt: str):
        self.t: G = None
        self.w: F = None
        self.q: F = None
        self.v: C = None
        self.r: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: H = None
        self.t: H = None
        self.p: H = None
        self.z: B = None
        self.s: B = None
        self.r: C = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.y: B = None
        self.x: F = None
        self.w: F = None
        self.txt = txt

j = A("j")
k = B("k")
d = C("d")
c = D("c")
a = E("a")
i = F("i")
f = G("f")
b = H("b")
e = G("e")

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

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

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

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

class E:
    def __init__(self, txt: str):
        self.t: G = None
        self.w: F = None
        self.q: F = None
        self.v: C = None
        self.r: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: H = None
        self.t: H = None
        self.p: H = None
        self.z: B = None
        self.s: B = None
        self.r: C = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.y: B = None
        self.x: F = None
        self.w: F = None
        self.txt = txt

j = A("j")
k = B("k")
d = C("d")
c = D("c")
a = E("a")
i = F("i")
f = G("f")
b = H("b")
e = G("e")

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