class A:
    def __init__(self, txt: str):
        self.t: E = None
        self.u: I = None
        self.z: I = None
        self.o: B = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.y: D = None
        self.o: G = None
        self.u: G = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.s: I = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.v: A = None
        self.u: F = None
        self.w: B = None
        self.r: G = None
        self.z: A = None
        self.s: B = None
        self.q: G = None
        self.o: D = None
        self.txt = txt

j = A("j")
c = B("c")
d = C("d")
i = D("i")
e = E("e")
b = F("b")
l = G("l")
g = H("g")
a = I("a")

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

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

class C:
    def __init__(self, txt: str):
        self.y: D = None
        self.o: G = None
        self.u: G = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.s: I = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.v: A = None
        self.u: F = None
        self.w: B = None
        self.r: G = None
        self.z: A = None
        self.s: B = None
        self.q: G = None
        self.o: D = None
        self.txt = txt

j = A("j")
c = B("c")
d = C("d")
i = D("i")
e = E("e")
b = F("b")
l = G("l")
g = H("g")
a = I("a")

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