class A:
    def __init__(self, txt: str):
        self.r: B = None
        self.p: F = None
        self.x: I = None
        self.z: E = None
        self.t: J = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.o: I = None
        self.z: F = None
        self.t: I = None
        self.v: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.x: B = None
        self.w: G = None
        self.t: H = None
        self.r: B = None
        self.v: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.o: F = None
        self.y: F = None
        self.v: B = None
        self.w: G = None
        self.u: J = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.y: F = None
        self.p: J = None
        self.w: I = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.p: J = None
        self.w: B = None
        self.v: B = None
        self.r: C = None
        self.z: G = None
        self.u: B = None
        self.q: I = None
        self.x: C = None
        self.s: A = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.z: B = None
        self.t: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.s: D = None
        self.x: G = None
        self.q: E = None
        self.z: I = None
        self.w: J = None
        self.o: E = None
        self.v: J = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.q: E = None
        self.u: C = None
        self.t: F = None
        self.z: H = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.t: D = None
        self.o: G = None
        self.z: C = None
        self.v: F = None
        self.y: A = None
        self.q: I = None
        self.r: G = None
        self.w: E = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.o: I = None
        self.z: F = None
        self.t: I = None
        self.v: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.x: B = None
        self.w: G = None
        self.t: H = None
        self.r: B = None
        self.v: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.o: F = None
        self.y: F = None
        self.v: B = None
        self.w: G = None
        self.u: J = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.y: F = None
        self.p: J = None
        self.w: I = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.p: J = None
        self.w: B = None
        self.v: B = None
        self.r: C = None
        self.z: G = None
        self.u: B = None
        self.q: I = None
        self.x: C = None
        self.s: A = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.z: B = None
        self.t: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.s: D = None
        self.x: G = None
        self.q: E = None
        self.z: I = None
        self.w: J = None
        self.o: E = None
        self.v: J = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.q: E = None
        self.u: C = None
        self.t: F = None
        self.z: H = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.t: D = None
        self.o: G = None
        self.z: C = None
        self.v: F = None
        self.y: A = None
        self.q: I = None
        self.r: G = None
        self.w: E = None
        self.txt = txt

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

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