class A:
    def __init__(self, txt: str):
        self.t: G = None
        self.s: H = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.v: G = None
        self.u: G = None
        self.y: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.r: G = None
        self.z: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: I = None
        self.r: G = None
        self.t: C = None
        self.v: C = None
        self.u: B = None
        self.q: F = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.q: D = None
        self.r: A = None
        self.x: A = None
        self.v: G = None
        self.o: B = None
        self.z: I = None
        self.y: D = None
        self.u: A = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.x: F = None
        self.q: B = None
        self.z: A = None
        self.y: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.z: B = None
        self.u: A = None
        self.q: I = None
        self.s: F = None
        self.o: F = None
        self.r: F = None
        self.t: I = None
        self.x: F = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.w: H = None
        self.v: A = None
        self.o: C = None
        self.s: H = None
        self.p: E = None
        self.txt = txt

j = A("j")
i = B("i")
m = C("m")
d = D("d")
k = E("k")
g = F("g")
e = G("e")
n = H("n")
a = I("a")

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

class B:
    def __init__(self, txt: str):
        self.v: G = None
        self.u: G = None
        self.y: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.r: G = None
        self.z: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: I = None
        self.r: G = None
        self.t: C = None
        self.v: C = None
        self.u: B = None
        self.q: F = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.q: D = None
        self.r: A = None
        self.x: A = None
        self.v: G = None
        self.o: B = None
        self.z: I = None
        self.y: D = None
        self.u: A = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.x: F = None
        self.q: B = None
        self.z: A = None
        self.y: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.z: B = None
        self.u: A = None
        self.q: I = None
        self.s: F = None
        self.o: F = None
        self.r: F = None
        self.t: I = None
        self.x: F = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.w: H = None
        self.v: A = None
        self.o: C = None
        self.s: H = None
        self.p: E = None
        self.txt = txt

j = A("j")
i = B("i")
m = C("m")
d = D("d")
k = E("k")
g = F("g")
e = G("e")
n = H("n")
a = I("a")

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