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

class B:
    def __init__(self, txt: str):
        self.r: D = None
        self.q: F = None
        self.p: J = None
        self.z: E = None
        self.w: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.z: D = None
        self.r: I = None
        self.o: H = None
        self.q: D = None
        self.v: G = None
        self.x: F = None
        self.w: G = None
        self.txt = txt

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

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

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

class G:
    def __init__(self, txt: str):
        self.x: F = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.t: C = None
        self.x: A = None
        self.q: H = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.r: D = None
        self.q: F = None
        self.p: J = None
        self.z: E = None
        self.w: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.z: D = None
        self.r: I = None
        self.o: H = None
        self.q: D = None
        self.v: G = None
        self.x: F = None
        self.w: G = None
        self.txt = txt

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

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

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

class G:
    def __init__(self, txt: str):
        self.x: F = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.t: C = None
        self.x: A = None
        self.q: H = None
        self.txt = txt

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

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

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