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

class B:
    def __init__(self, txt: str):
        self.o: D = None
        self.s: A = None
        self.v: F = None
        self.z: C = None
        self.x: G = None
        self.p: E = None
        self.u: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.v: G = None
        self.x: E = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.p: C = None
        self.v: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.s: E = None
        self.txt = txt

d = A("d")
c = B("c")
k = C("k")
b = D("b")
n = E("n")
a = F("a")
g = G("g")
e = E("e")
j = A("j")

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

class B:
    def __init__(self, txt: str):
        self.o: D = None
        self.s: A = None
        self.v: F = None
        self.z: C = None
        self.x: G = None
        self.p: E = None
        self.u: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.v: G = None
        self.x: E = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.p: C = None
        self.v: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.s: E = None
        self.txt = txt

d = A("d")
c = B("c")
k = C("k")
b = D("b")
n = E("n")
a = F("a")
g = G("g")
e = E("e")
j = A("j")

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