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

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

class C:
    def __init__(self, txt: str):
        self.w: A = None
        self.x: A = None
        self.r: G = None
        self.s: B = None
        self.y: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.o: G = None
        self.u: C = None
        self.w: B = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.t: A = None
        self.p: H = None
        self.x: I = None
        self.s: C = None
        self.w: B = None
        self.q: I = None
        self.txt = txt

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

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

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

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

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

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

class C:
    def __init__(self, txt: str):
        self.w: A = None
        self.x: A = None
        self.r: G = None
        self.s: B = None
        self.y: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.o: G = None
        self.u: C = None
        self.w: B = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.t: A = None
        self.p: H = None
        self.x: I = None
        self.s: C = None
        self.w: B = None
        self.q: I = None
        self.txt = txt

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

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

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

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

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