class A:
    def __init__(self, txt: str):
        self.x: D = None
        self.t: G = None
        self.v: I = None
        self.s: C = None
        self.o: I = None
        self.q: C = None
        self.w: C = None
        self.txt = txt

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.q: H = None
        self.s: B = None
        self.p: G = None
        self.o: J = None
        self.r: A = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.u: D = None
        self.r: B = None
        self.v: B = None
        self.p: C = None
        self.q: J = None
        self.x: C = None
        self.w: G = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.y: J = None
        self.s: E = None
        self.txt = txt

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

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

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

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.q: H = None
        self.s: B = None
        self.p: G = None
        self.o: J = None
        self.r: A = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.u: D = None
        self.r: B = None
        self.v: B = None
        self.p: C = None
        self.q: J = None
        self.x: C = None
        self.w: G = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.y: J = None
        self.s: E = None
        self.txt = txt

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

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

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