class A:
    def __init__(self, txt: str):
        self.v: H = None
        self.y: F = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.o: I = None
        self.q: J = None
        self.v: G = None
        self.p: F = None
        self.y: F = None
        self.w: D = None
        self.t: E = None
        self.u: F = None
        self.s: A = None
        self.txt = txt

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

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

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

class G:
    def __init__(self, txt: str):
        self.r: H = None
        self.z: H = None
        self.o: C = None
        self.v: C = None
        self.t: F = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.x: E = None
        self.u: F = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.u: H = None
        self.r: A = None
        self.z: E = None
        self.w: D = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.o: I = None
        self.q: J = None
        self.v: G = None
        self.p: F = None
        self.y: F = None
        self.w: D = None
        self.t: E = None
        self.u: F = None
        self.s: A = None
        self.txt = txt

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

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

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

class G:
    def __init__(self, txt: str):
        self.r: H = None
        self.z: H = None
        self.o: C = None
        self.v: C = None
        self.t: F = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.x: E = None
        self.u: F = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.u: H = None
        self.r: A = None
        self.z: E = None
        self.w: D = None
        self.txt = txt

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

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