class A:
    def __init__(self, txt: str):
        self.t: F = None
        self.txt = txt

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.t: B = None
        self.u: B = None
        self.z: A = None
        self.txt = txt

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

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

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

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

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

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.t: B = None
        self.u: B = None
        self.z: A = None
        self.txt = txt

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

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

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

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

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