class A:
    def __init__(self, txt: str):
        self.v: F = None
        self.p: H = None
        self.t: H = None
        self.q: I = None
        self.z: I = None
        self.txt = txt

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

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

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

class E:
    def __init__(self, txt: str):
        self.p: C = None
        self.z: A = None
        self.y: B = None
        self.q: A = None
        self.r: I = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.p: G = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.s: E = None
        self.u: C = None
        self.p: D = None
        self.z: F = None
        self.q: E = None
        self.v: E = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.x: H = None
        self.txt = txt

m = A("m")
l = B("l")
i = C("i")
c = D("c")
j = E("j")
k = F("k")
b = G("b")
d = H("d")
e = I("e")
h = E("h")

m.v = k
m.p = d
m.t = d
m.q = e
m.z = e
l.y = m
i.t = d
i.y = l
c.r = b
c.s = d
j.p = i
j.z = m
j.q = m
j.y = l
j.r = e
k.p = b
b.s = h
b.q = h
b.v = h
b.u = i
b.p = c
b.z = k
d.q = m
d.u = e
e.x = d
h.p = i
h.z = m
h.q = m
h.y = l
h.r = e
assert h.y.y.v.p.u.t.q.p.u.x.txt == "
class A:
    def __init__(self, txt: str):
        self.v: F = None
        self.p: H = None
        self.t: H = None
        self.q: I = None
        self.z: I = None
        self.txt = txt

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

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

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

class E:
    def __init__(self, txt: str):
        self.p: C = None
        self.z: A = None
        self.y: B = None
        self.q: A = None
        self.r: I = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.p: G = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.s: E = None
        self.u: C = None
        self.p: D = None
        self.z: F = None
        self.q: E = None
        self.v: E = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.x: H = None
        self.txt = txt

m = A("m")
l = B("l")
i = C("i")
c = D("c")
j = E("j")
k = F("k")
b = G("b")
d = H("d")
e = I("e")
h = E("h")

m.v = k
m.p = d
m.t = d
m.q = e
m.z = e
l.y = m
i.t = d
i.y = l
c.r = b
c.s = d
j.p = i
j.z = m
j.q = m
j.y = l
j.r = e
k.p = b
b.s = h
b.q = h
b.v = h
b.u = i
b.p = c
b.z = k
d.q = m
d.u = e
e.x = d
h.p = i
h.z = m
h.q = m
h.y = l
h.r = e
assert h.y.y.v.p.u.t.q.p.u.x.txt == "d"