class A:
    def __init__(self, txt: str):
        self.t: H = None
        self.x: B = None
        self.u: D = None
        self.r: B = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.r: G = None
        self.s: D = None
        self.v: G = None
        self.x: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.y: A = None
        self.s: D = None
        self.v: E = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: C = None
        self.s: F = None
        self.o: H = None
        self.x: C = None
        self.y: H = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.z: C = None
        self.y: C = None
        self.p: E = None
        self.x: H = None
        self.s: A = None
        self.r: C = None
        self.o: C = None
        self.txt = txt

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

j = A("j")
d = B("d")
m = C("m")
a = D("a")
c = E("c")
k = F("k")
f = G("f")
h = H("h")
b = A("b")

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

class B:
    def __init__(self, txt: str):
        self.r: G = None
        self.s: D = None
        self.v: G = None
        self.x: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.y: A = None
        self.s: D = None
        self.v: E = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: C = None
        self.s: F = None
        self.o: H = None
        self.x: C = None
        self.y: H = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.z: C = None
        self.y: C = None
        self.p: E = None
        self.x: H = None
        self.s: A = None
        self.r: C = None
        self.o: C = None
        self.txt = txt

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

j = A("j")
d = B("d")
m = C("m")
a = D("a")
c = E("c")
k = F("k")
f = G("f")
h = H("h")
b = A("b")

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