class A:
    def __init__(self, txt: str):
        self.t: D = None
        self.v: I = None
        self.s: I = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.s: E = None
        self.z: E = None
        self.w: D = None
        self.q: I = None
        self.x: G = None
        self.o: G = None
        self.u: C = None
        self.p: C = None
        self.txt = txt

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

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

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

class F:
    def __init__(self, txt: str):
        self.q: A = None
        self.x: H = None
        self.t: D = None
        self.s: B = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.u: A = None
        self.o: I = None
        self.p: C = None
        self.txt = txt

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

j = A("j")
f = B("f")
g = C("g")
l = D("l")
i = E("i")
d = F("d")
b = G("b")
c = H("c")
n = I("n")
e = H("e")

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

class B:
    def __init__(self, txt: str):
        self.s: E = None
        self.z: E = None
        self.w: D = None
        self.q: I = None
        self.x: G = None
        self.o: G = None
        self.u: C = None
        self.p: C = None
        self.txt = txt

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

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

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

class F:
    def __init__(self, txt: str):
        self.q: A = None
        self.x: H = None
        self.t: D = None
        self.s: B = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.u: A = None
        self.o: I = None
        self.p: C = None
        self.txt = txt

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

j = A("j")
f = B("f")
g = C("g")
l = D("l")
i = E("i")
d = F("d")
b = G("b")
c = H("c")
n = I("n")
e = H("e")

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