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

class B:
    def __init__(self, txt: str):
        self.t: C = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.s: D = None
        self.p: F = None
        self.w: H = None
        self.y: D = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.r: D = None
        self.txt = txt

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

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

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

class I:
    def __init__(self, txt: str):
        self.t: E = None
        self.p: F = None
        self.u: B = None
        self.v: B = None
        self.w: B = None
        self.o: E = None
        self.txt = txt

b = A("b")
m = B("m")
n = C("n")
d = D("d")
e = E("e")
c = F("c")
f = G("f")
a = H("a")
j = I("j")

b.v = f
b.w = c
b.s = a
b.r = a
b.u = n
b.p = j
m.t = n
n.s = d
n.y = d
n.p = c
n.w = a
d.v = c
d.s = a
e.r = d
c.s = j
c.p = e
f.t = c
f.v = b
f.p = m
f.y = j
f.u = j
a.q = n
a.w = c
a.u = j
j.t = e
j.o = e
j.p = c
j.u = m
j.v = m
j.w = m
assert f.p.t.p.s.p.p.r.v.txt == "
class A:
    def __init__(self, txt: str):
        self.v: G = None
        self.w: F = None
        self.s: H = None
        self.u: C = None
        self.r: H = None
        self.p: I = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.t: C = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.s: D = None
        self.p: F = None
        self.w: H = None
        self.y: D = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.r: D = None
        self.txt = txt

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

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

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

class I:
    def __init__(self, txt: str):
        self.t: E = None
        self.p: F = None
        self.u: B = None
        self.v: B = None
        self.w: B = None
        self.o: E = None
        self.txt = txt

b = A("b")
m = B("m")
n = C("n")
d = D("d")
e = E("e")
c = F("c")
f = G("f")
a = H("a")
j = I("j")

b.v = f
b.w = c
b.s = a
b.r = a
b.u = n
b.p = j
m.t = n
n.s = d
n.y = d
n.p = c
n.w = a
d.v = c
d.s = a
e.r = d
c.s = j
c.p = e
f.t = c
f.v = b
f.p = m
f.y = j
f.u = j
a.q = n
a.w = c
a.u = j
j.t = e
j.o = e
j.p = c
j.u = m
j.v = m
j.w = m
assert f.p.t.p.s.p.p.r.v.txt == "c"