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

class B:
    def __init__(self, txt: str):
        self.x: C = None
        self.v: E = None
        self.w: I = None
        self.txt = txt

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

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

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

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

class G:
    def __init__(self, txt: str):
        self.p: E = None
        self.z: H = None
        self.x: F = None
        self.s: A = None
        self.q: C = None
        self.v: E = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.r: C = None
        self.t: C = None
        self.p: B = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.x: B = None
        self.p: E = None
        self.q: D = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.x: C = None
        self.v: E = None
        self.w: I = None
        self.txt = txt

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

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

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

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

class G:
    def __init__(self, txt: str):
        self.p: E = None
        self.z: H = None
        self.x: F = None
        self.s: A = None
        self.q: C = None
        self.v: E = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.r: C = None
        self.t: C = None
        self.p: B = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.x: B = None
        self.p: E = None
        self.q: D = None
        self.txt = txt

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

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