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

class B:
    def __init__(self, txt: str):
        self.p: E = None
        self.t: E = None
        self.y: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: D = None
        self.z: D = None
        self.t: F = None
        self.x: E = None
        self.r: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: F = None
        self.r: C = None
        self.q: F = None
        self.t: G = None
        self.w: F = None
        self.u: A = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.r: G = None
        self.z: C = None
        self.x: B = None
        self.y: C = None
        self.u: E = None
        self.txt = txt

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

h = A("h")
e = B("e")
g = C("g")
j = D("j")
a = E("a")
c = F("c")
l = G("l")
m = E("m")

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

class B:
    def __init__(self, txt: str):
        self.p: E = None
        self.t: E = None
        self.y: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: D = None
        self.z: D = None
        self.t: F = None
        self.x: E = None
        self.r: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: F = None
        self.r: C = None
        self.q: F = None
        self.t: G = None
        self.w: F = None
        self.u: A = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.r: G = None
        self.z: C = None
        self.x: B = None
        self.y: C = None
        self.u: E = None
        self.txt = txt

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

h = A("h")
e = B("e")
g = C("g")
j = D("j")
a = E("a")
c = F("c")
l = G("l")
m = E("m")

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