class A:
    def __init__(self, txt: str):
        self.x: J = None
        self.z: J = None
        self.w: E = None
        self.p: J = None
        self.s: G = None
        self.q: E = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.u: F = None
        self.y: A = None
        self.z: E = None
        self.t: C = None
        self.r: I = None
        self.o: H = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.t: B = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.u: J = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.t: J = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.p: E = None
        self.q: H = None
        self.v: E = None
        self.txt = txt

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

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

class J:
    def __init__(self, txt: str):
        self.v: G = None
        self.s: G = None
        self.t: E = None
        self.txt = txt

g = A("g")
h = B("h")
m = C("m")
j = D("j")
a = E("a")
b = F("b")
f = G("f")
n = H("n")
k = I("k")
c = J("c")

g.x = c
g.z = c
g.p = c
g.w = a
g.q = a
g.s = f
h.u = b
h.y = g
h.z = a
h.t = m
h.r = k
h.o = n
m.t = h
j.t = n
j.v = n
j.x = a
j.s = a
j.w = k
j.y = k
j.z = h
j.r = h
j.o = f
j.p = f
a.u = c
b.t = c
f.p = a
f.v = a
f.q = n
n.x = f
n.o = f
n.w = a
n.t = a
n.r = g
n.u = g
n.p = j
n.v = j
n.q = k
n.s = k
k.s = m
c.v = f
c.s = f
c.t = a
assert j.y.s.t.z.u.t.u.v.txt == "
class A:
    def __init__(self, txt: str):
        self.x: J = None
        self.z: J = None
        self.w: E = None
        self.p: J = None
        self.s: G = None
        self.q: E = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.u: F = None
        self.y: A = None
        self.z: E = None
        self.t: C = None
        self.r: I = None
        self.o: H = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.t: B = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.u: J = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.t: J = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.p: E = None
        self.q: H = None
        self.v: E = None
        self.txt = txt

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

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

class J:
    def __init__(self, txt: str):
        self.v: G = None
        self.s: G = None
        self.t: E = None
        self.txt = txt

g = A("g")
h = B("h")
m = C("m")
j = D("j")
a = E("a")
b = F("b")
f = G("f")
n = H("n")
k = I("k")
c = J("c")

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