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

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

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

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

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

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

class G:
    def __init__(self, txt: str):
        self.w: B = None
        self.x: E = None
        self.s: A = None
        self.z: F = None
        self.u: G = None
        self.txt = txt

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

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

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

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

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

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

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

class G:
    def __init__(self, txt: str):
        self.w: B = None
        self.x: E = None
        self.s: A = None
        self.z: F = None
        self.u: G = None
        self.txt = txt

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

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