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

class B:
    def __init__(self, txt: str):
        self.x: D = None
        self.r: I = None
        self.p: C = None
        self.y: I = None
        self.z: A = None
        self.o: C = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.y: B = None
        self.t: I = None
        self.s: G = None
        self.w: B = None
        self.u: I = None
        self.v: A = None
        self.o: D = None
        self.p: F = None
        self.txt = txt

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

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

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

class G:
    def __init__(self, txt: str):
        self.t: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.r: G = None
        self.y: F = None
        self.t: G = None
        self.u: I = None
        self.v: D = None
        self.q: D = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.x: D = None
        self.r: I = None
        self.p: C = None
        self.y: I = None
        self.z: A = None
        self.o: C = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.y: B = None
        self.t: I = None
        self.s: G = None
        self.w: B = None
        self.u: I = None
        self.v: A = None
        self.o: D = None
        self.p: F = None
        self.txt = txt

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

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

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

class G:
    def __init__(self, txt: str):
        self.t: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.r: G = None
        self.y: F = None
        self.t: G = None
        self.u: I = None
        self.v: D = None
        self.q: D = None
        self.txt = txt

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

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

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