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

class B:
    def __init__(self, txt: str):
        self.y: D = None
        self.q: A = None
        self.r: E = None
        self.w: G = None
        self.v: A = None
        self.p: E = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.s: F = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.s: D = None
        self.r: E = None
        self.z: D = None
        self.x: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.t: A = None
        self.w: G = None
        self.o: H = None
        self.s: I = None
        self.y: I = None
        self.z: G = None
        self.p: A = None
        self.r: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.o: D = None
        self.s: G = None
        self.t: F = None
        self.u: C = None
        self.z: B = None
        self.q: I = None
        self.y: G = None
        self.r: I = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.y: D = None
        self.q: A = None
        self.r: E = None
        self.w: G = None
        self.v: A = None
        self.p: E = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.s: F = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.s: D = None
        self.r: E = None
        self.z: D = None
        self.x: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.t: A = None
        self.w: G = None
        self.o: H = None
        self.s: I = None
        self.y: I = None
        self.z: G = None
        self.p: A = None
        self.r: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.o: D = None
        self.s: G = None
        self.t: F = None
        self.u: C = None
        self.z: B = None
        self.q: I = None
        self.y: G = None
        self.r: I = None
        self.txt = txt

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

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

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