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

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

class C:
    def __init__(self, txt: str):
        self.p: F = None
        self.x: A = None
        self.z: I = None
        self.o: F = None
        self.v: I = None
        self.q: D = None
        self.w: E = None
        self.y: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: C = None
        self.u: H = None
        self.t: I = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.t: A = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.s: H = None
        self.u: I = None
        self.q: D = None
        self.t: H = None
        self.z: A = None
        self.p: E = None
        self.y: A = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.v: I = None
        self.u: A = None
        self.s: A = None
        self.txt = txt

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

j = A("j")
m = B("m")
g = C("g")
a = D("a")
h = E("h")
n = F("n")
b = G("b")
k = H("k")
c = I("c")

j.t = n
j.p = h
j.y = a
m.v = h
m.u = a
m.t = g
g.p = n
g.o = n
g.x = j
g.z = c
g.v = c
g.y = c
g.q = a
g.w = h
a.v = g
a.u = k
a.t = c
h.y = k
h.o = a
h.z = a
h.u = j
h.x = m
h.w = g
n.t = j
b.s = k
b.t = k
b.u = c
b.q = a
b.z = j
b.y = j
b.p = h
k.v = c
k.u = j
k.s = j
c.s = n
assert c.s.t.p.x.t.z.s.t.txt == "
class A:
    def __init__(self, txt: str):
        self.t: F = None
        self.p: E = None
        self.y: D = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.p: F = None
        self.x: A = None
        self.z: I = None
        self.o: F = None
        self.v: I = None
        self.q: D = None
        self.w: E = None
        self.y: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: C = None
        self.u: H = None
        self.t: I = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.t: A = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.s: H = None
        self.u: I = None
        self.q: D = None
        self.t: H = None
        self.z: A = None
        self.p: E = None
        self.y: A = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.v: I = None
        self.u: A = None
        self.s: A = None
        self.txt = txt

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

j = A("j")
m = B("m")
g = C("g")
a = D("a")
h = E("h")
n = F("n")
b = G("b")
k = H("k")
c = I("c")

j.t = n
j.p = h
j.y = a
m.v = h
m.u = a
m.t = g
g.p = n
g.o = n
g.x = j
g.z = c
g.v = c
g.y = c
g.q = a
g.w = h
a.v = g
a.u = k
a.t = c
h.y = k
h.o = a
h.z = a
h.u = j
h.x = m
h.w = g
n.t = j
b.s = k
b.t = k
b.u = c
b.q = a
b.z = j
b.y = j
b.p = h
k.v = c
k.u = j
k.s = j
c.s = n
assert c.s.t.p.x.t.z.s.t.txt == "j"