class A:
    def __init__(self, txt: str):
        self.x: H = None
        self.y: C = None
        self.r: I = None
        self.u: F = None
        self.p: B = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.x: H = None
        self.v: G = None
        self.s: E = None
        self.y: I = None
        self.z: C = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.w: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.s: G = None
        self.u: B = None
        self.o: D = None
        self.x: F = None
        self.w: I = None
        self.z: B = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.o: D = None
        self.v: E = None
        self.y: H = None
        self.q: C = None
        self.u: D = None
        self.s: E = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.r: F = None
        self.p: B = None
        self.t: G = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.x: H = None
        self.v: G = None
        self.s: E = None
        self.y: I = None
        self.z: C = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.w: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.s: G = None
        self.u: B = None
        self.o: D = None
        self.x: F = None
        self.w: I = None
        self.z: B = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.o: D = None
        self.v: E = None
        self.y: H = None
        self.q: C = None
        self.u: D = None
        self.s: E = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.r: F = None
        self.p: B = None
        self.t: G = None
        self.txt = txt

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

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