class A:
    def __init__(self, txt: str):
        self.t: E = None
        self.s: F = None
        self.r: I = None
        self.q: I = None
        self.x: E = None
        self.w: B = None
        self.v: B = None
        self.y: B = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.q: G = None
        self.v: H = None
        self.u: I = None
        self.s: A = None
        self.z: C = None
        self.o: I = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.v: I = None
        self.s: E = None
        self.t: E = None
        self.u: H = None
        self.w: H = None
        self.p: I = None
        self.r: I = None
        self.o: B = None
        self.q: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.r: A = None
        self.u: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.o: B = None
        self.y: F = None
        self.z: G = None
        self.w: C = None
        self.u: H = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.u: I = None
        self.y: E = None
        self.r: C = None
        self.w: F = None
        self.v: D = None
        self.z: G = None
        self.s: D = None
        self.txt = txt

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

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

f.t = k
f.x = k
f.s = b
f.r = c
f.q = c
f.w = h
f.v = h
f.y = h
h.q = m
h.v = d
h.u = c
h.o = c
h.s = f
h.z = j
j.v = c
j.p = c
j.r = c
j.q = c
j.s = k
j.t = k
j.u = d
j.w = d
j.o = h
a.r = f
a.u = b
k.o = h
k.y = n
k.z = m
k.w = j
k.u = d
n.x = k
n.q = k
n.s = k
n.o = d
n.t = h
n.u = m
n.z = f
n.p = a
m.o = c
m.q = b
m.p = b
m.v = b
m.y = f
m.t = k
d.u = c
d.y = k
d.r = j
d.w = n
d.v = a
d.s = a
d.z = m
c.u = n
c.q = m
c.s = m
c.x = m
c.o = a
c.w = k
c.t = b
c.r = j
c.v = f
b.x = k
b.q = k
b.s = k
b.o = d
b.t = h
b.u = m
b.z = f
b.p = a
assert m.y.q.r.t.w.p.txt == "
class A:
    def __init__(self, txt: str):
        self.t: E = None
        self.s: F = None
        self.r: I = None
        self.q: I = None
        self.x: E = None
        self.w: B = None
        self.v: B = None
        self.y: B = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.q: G = None
        self.v: H = None
        self.u: I = None
        self.s: A = None
        self.z: C = None
        self.o: I = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.v: I = None
        self.s: E = None
        self.t: E = None
        self.u: H = None
        self.w: H = None
        self.p: I = None
        self.r: I = None
        self.o: B = None
        self.q: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.r: A = None
        self.u: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.o: B = None
        self.y: F = None
        self.z: G = None
        self.w: C = None
        self.u: H = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.u: I = None
        self.y: E = None
        self.r: C = None
        self.w: F = None
        self.v: D = None
        self.z: G = None
        self.s: D = None
        self.txt = txt

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

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

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