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

class B:
    def __init__(self, txt: str):
        self.o: C = None
        self.p: D = None
        self.q: C = None
        self.y: G = None
        self.w: A = None
        self.s: E = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.s: C = None
        self.y: D = None
        self.u: B = None
        self.q: B = None
        self.txt = txt

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

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

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

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

class B:
    def __init__(self, txt: str):
        self.o: C = None
        self.p: D = None
        self.q: C = None
        self.y: G = None
        self.w: A = None
        self.s: E = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.s: C = None
        self.y: D = None
        self.u: B = None
        self.q: B = None
        self.txt = txt

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

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

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

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