class A:
    def __init__(self, txt: str):
        self.p: G = None
        self.w: I = None
        self.z: G = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.u: G = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: A = None
        self.u: E = None
        self.q: G = None
        self.z: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: C = None
        self.o: F = None
        self.z: D = None
        self.q: H = None
        self.s: F = None
        self.t: C = None
        self.x: I = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.x: H = None
        self.o: J = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.t: C = None
        self.x: J = None
        self.o: J = None
        self.r: A = None
        self.p: D = None
        self.q: D = None
        self.u: G = None
        self.z: A = None
        self.y: G = None
        self.s: F = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.x: E = None
        self.q: J = None
        self.w: D = None
        self.y: D = None
        self.t: C = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.w: D = None
        self.q: F = None
        self.p: C = None
        self.r: B = None
        self.t: B = None
        self.z: F = None
        self.x: E = None
        self.s: E = None
        self.o: D = None
        self.v: C = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.u: G = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: A = None
        self.u: E = None
        self.q: G = None
        self.z: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: C = None
        self.o: F = None
        self.z: D = None
        self.q: H = None
        self.s: F = None
        self.t: C = None
        self.x: I = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.x: H = None
        self.o: J = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.t: C = None
        self.x: J = None
        self.o: J = None
        self.r: A = None
        self.p: D = None
        self.q: D = None
        self.u: G = None
        self.z: A = None
        self.y: G = None
        self.s: F = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.x: E = None
        self.q: J = None
        self.w: D = None
        self.y: D = None
        self.t: C = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.w: D = None
        self.q: F = None
        self.p: C = None
        self.r: B = None
        self.t: B = None
        self.z: F = None
        self.x: E = None
        self.s: E = None
        self.o: D = None
        self.v: C = None
        self.txt = txt

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

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