class A:
    def __init__(self, txt: str):
        self.p: B = None
        self.z: C = None
        self.o: B = None
        self.t: F = None
        self.r: D = None
        self.w: F = None
        self.x: G = None
        self.txt = txt

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.r: G = None
        self.z: C = None
        self.s: G = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.r: A = None
        self.y: B = None
        self.o: E = None
        self.txt = txt

d = A("d")
i = B("i")
b = C("b")
k = D("k")
e = E("e")
h = F("h")
g = G("g")
j = F("j")
l = D("l")
a = F("a")

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

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.r: G = None
        self.z: C = None
        self.s: G = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.r: A = None
        self.y: B = None
        self.o: E = None
        self.txt = txt

d = A("d")
i = B("i")
b = C("b")
k = D("k")
e = E("e")
h = F("h")
g = G("g")
j = F("j")
l = D("l")
a = F("a")

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