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

class B:
    def __init__(self, txt: str):
        self.w: F = None
        self.q: F = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.u: H = None
        self.y: C = None
        self.t: F = None
        self.s: I = None
        self.x: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.r: A = None
        self.z: A = None
        self.o: I = None
        self.t: I = None
        self.s: I = None
        self.q: I = None
        self.w: I = None
        self.v: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: I = None
        self.t: A = None
        self.v: C = None
        self.x: E = None
        self.p: H = None
        self.u: J = None
        self.o: C = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.w: A = None
        self.s: I = None
        self.r: C = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.q: G = None
        self.w: E = None
        self.y: D = None
        self.u: H = None
        self.t: D = None
        self.r: H = None
        self.z: A = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.y: A = None
        self.w: B = None
        self.r: F = None
        self.u: E = None
        self.v: G = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.w: F = None
        self.q: F = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.u: H = None
        self.y: C = None
        self.t: F = None
        self.s: I = None
        self.x: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.r: A = None
        self.z: A = None
        self.o: I = None
        self.t: I = None
        self.s: I = None
        self.q: I = None
        self.w: I = None
        self.v: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: I = None
        self.t: A = None
        self.v: C = None
        self.x: E = None
        self.p: H = None
        self.u: J = None
        self.o: C = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.w: A = None
        self.s: I = None
        self.r: C = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.q: G = None
        self.w: E = None
        self.y: D = None
        self.u: H = None
        self.t: D = None
        self.r: H = None
        self.z: A = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.y: A = None
        self.w: B = None
        self.r: F = None
        self.u: E = None
        self.v: G = None
        self.txt = txt

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

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