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

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

class C:
    def __init__(self, txt: str):
        self.w: E = None
        self.txt = txt

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

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

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

class G:
    def __init__(self, txt: str):
        self.z: B = None
        self.r: B = None
        self.t: F = None
        self.x: F = None
        self.y: E = None
        self.q: B = None
        self.s: B = None
        self.txt = txt

n = A("n")
e = B("e")
m = C("m")
j = D("j")
k = E("k")
b = F("b")
g = G("g")
c = D("c")
f = F("f")
i = F("i")

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

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

class C:
    def __init__(self, txt: str):
        self.w: E = None
        self.txt = txt

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

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

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

class G:
    def __init__(self, txt: str):
        self.z: B = None
        self.r: B = None
        self.t: F = None
        self.x: F = None
        self.y: E = None
        self.q: B = None
        self.s: B = None
        self.txt = txt

n = A("n")
e = B("e")
m = C("m")
j = D("j")
k = E("k")
b = F("b")
g = G("g")
c = D("c")
f = F("f")
i = F("i")

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