class A:
    def __init__(self, txt: str):
        self.v: A = None
        self.t: E = None
        self.o: D = None
        self.p: E = None
        self.q: D = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.p: B = None
        self.x: E = None
        self.t: E = None
        self.o: E = None
        self.y: E = None
        self.r: A = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.w: D = None
        self.p: C = None
        self.u: C = None
        self.q: B = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.x: B = None
        self.s: D = None
        self.txt = txt

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

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

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

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

class C:
    def __init__(self, txt: str):
        self.p: B = None
        self.x: E = None
        self.t: E = None
        self.o: E = None
        self.y: E = None
        self.r: A = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.w: D = None
        self.p: C = None
        self.u: C = None
        self.q: B = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.x: B = None
        self.s: D = None
        self.txt = txt

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

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

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