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

class B:
    def __init__(self, txt: str):
        self.y: H = None
        self.t: D = None
        self.v: D = None
        self.p: G = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.u: C = None
        self.p: G = None
        self.s: I = None
        self.w: C = None
        self.r: D = None
        self.z: I = None
        self.y: B = None
        self.x: H = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.o: C = None
        self.p: I = None
        self.x: E = None
        self.v: I = None
        self.t: G = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.x: D = None
        self.q: C = None
        self.r: D = None
        self.txt = txt

d = A("d")
a = B("a")
g = C("g")
m = D("m")
l = E("l")
f = F("f")
h = G("h")
i = H("i")
k = I("k")
c = D("c")

d.u = k
d.z = k
d.q = k
d.v = k
d.y = a
d.r = l
d.x = l
d.p = l
d.o = i
a.y = i
a.t = c
a.v = m
a.p = h
g.w = l
g.t = i
m.p = h
m.x = h
m.v = c
m.q = c
m.y = f
m.u = a
m.t = a
m.o = g
m.r = l
l.u = g
l.w = g
l.p = h
l.s = k
l.z = k
l.r = c
l.y = a
l.x = i
f.x = i
f.p = g
h.y = d
i.o = g
i.p = k
i.v = k
i.x = l
i.t = h
k.x = c
k.q = g
k.r = m
c.p = h
c.x = h
c.v = m
c.q = m
c.y = f
c.u = a
c.t = a
c.o = g
c.r = l
assert d.o.o.t.txt == "
class A:
    def __init__(self, txt: str):
        self.u: I = None
        self.y: B = None
        self.r: E = None
        self.x: E = None
        self.p: E = None
        self.z: I = None
        self.o: H = None
        self.q: I = None
        self.v: I = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.y: H = None
        self.t: D = None
        self.v: D = None
        self.p: G = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.u: C = None
        self.p: G = None
        self.s: I = None
        self.w: C = None
        self.r: D = None
        self.z: I = None
        self.y: B = None
        self.x: H = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.o: C = None
        self.p: I = None
        self.x: E = None
        self.v: I = None
        self.t: G = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.x: D = None
        self.q: C = None
        self.r: D = None
        self.txt = txt

d = A("d")
a = B("a")
g = C("g")
m = D("m")
l = E("l")
f = F("f")
h = G("h")
i = H("i")
k = I("k")
c = D("c")

d.u = k
d.z = k
d.q = k
d.v = k
d.y = a
d.r = l
d.x = l
d.p = l
d.o = i
a.y = i
a.t = c
a.v = m
a.p = h
g.w = l
g.t = i
m.p = h
m.x = h
m.v = c
m.q = c
m.y = f
m.u = a
m.t = a
m.o = g
m.r = l
l.u = g
l.w = g
l.p = h
l.s = k
l.z = k
l.r = c
l.y = a
l.x = i
f.x = i
f.p = g
h.y = d
i.o = g
i.p = k
i.v = k
i.x = l
i.t = h
k.x = c
k.q = g
k.r = m
c.p = h
c.x = h
c.v = m
c.q = m
c.y = f
c.u = a
c.t = a
c.o = g
c.r = l
assert d.o.o.t.txt == "i"