class A:
    def __init__(self, txt: str):
        self.u: E = None
        self.z: I = None
        self.o: F = None
        self.p: E = None
        self.v: C = None
        self.x: G = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.y: G = None
        self.q: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.x: I = None
        self.s: B = None
        self.u: I = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.z: C = None
        self.w: H = None
        self.s: H = None
        self.r: H = None
        self.y: B = None
        self.v: E = None
        self.q: C = None
        self.u: G = None
        self.txt = txt

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

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

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

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

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

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

class C:
    def __init__(self, txt: str):
        self.y: G = None
        self.q: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.x: I = None
        self.s: B = None
        self.u: I = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.z: C = None
        self.w: H = None
        self.s: H = None
        self.r: H = None
        self.y: B = None
        self.v: E = None
        self.q: C = None
        self.u: G = None
        self.txt = txt

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

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

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

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

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