class A:
    def __init__(self, txt: str):
        self.u: E = None
        self.q: I = None
        self.t: H = None
        self.z: E = None
        self.s: E = None
        self.v: E = None
        self.p: G = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.y: G = None
        self.q: G = None
        self.t: G = None
        self.r: B = None
        self.s: F = None
        self.p: E = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.w: A = None
        self.x: I = None
        self.z: G = None
        self.v: A = None
        self.p: F = None
        self.r: H = None
        self.s: F = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.q: I = None
        self.u: G = None
        self.o: B = None
        self.y: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.w: E = None
        self.s: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.w: D = None
        self.txt = txt

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

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

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

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

class C:
    def __init__(self, txt: str):
        self.y: G = None
        self.q: G = None
        self.t: G = None
        self.r: B = None
        self.s: F = None
        self.p: E = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.w: A = None
        self.x: I = None
        self.z: G = None
        self.v: A = None
        self.p: F = None
        self.r: H = None
        self.s: F = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.q: I = None
        self.u: G = None
        self.o: B = None
        self.y: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.w: E = None
        self.s: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.w: D = None
        self.txt = txt

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

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

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