class A:
    def __init__(self, txt: str):
        self.t: D = None
        self.u: H = None
        self.v: D = None
        self.r: E = None
        self.s: E = None
        self.p: E = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.y: J = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.o: D = None
        self.p: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.p: J = None
        self.x: B = None
        self.q: E = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.s: F = None
        self.r: F = None
        self.z: A = None
        self.t: A = None
        self.x: C = None
        self.v: G = None
        self.q: B = None
        self.w: F = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.w: B = None
        self.t: E = None
        self.v: E = None
        self.x: J = None
        self.z: J = None
        self.p: F = None
        self.txt = txt

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

l = A("l")
h = B("h")
g = C("g")
a = D("a")
j = E("j")
i = F("i")
k = G("k")
c = H("c")
n = I("n")
e = J("e")

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

class B:
    def __init__(self, txt: str):
        self.y: J = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.o: D = None
        self.p: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.p: J = None
        self.x: B = None
        self.q: E = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.s: F = None
        self.r: F = None
        self.z: A = None
        self.t: A = None
        self.x: C = None
        self.v: G = None
        self.q: B = None
        self.w: F = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.w: B = None
        self.t: E = None
        self.v: E = None
        self.x: J = None
        self.z: J = None
        self.p: F = None
        self.txt = txt

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

l = A("l")
h = B("h")
g = C("g")
a = D("a")
j = E("j")
i = F("i")
k = G("k")
c = H("c")
n = I("n")
e = J("e")

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