class A:
    def __init__(self, txt: str):
        self.q: B = None
        self.x: H = None
        self.o: G = None
        self.v: H = None
        self.s: F = None
        self.t: C = None
        self.z: E = None
        self.p: G = None
        self.y: D = None
        self.txt = txt

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

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

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

class E:
    def __init__(self, txt: str):
        self.q: G = None
        self.s: D = None
        self.t: I = None
        self.u: I = None
        self.z: C = None
        self.w: C = None
        self.r: D = None
        self.v: D = None
        self.x: B = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.u: D = None
        self.y: I = None
        self.r: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.w: E = None
        self.o: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.p: I = None
        self.s: E = None
        self.u: B = None
        self.o: F = None
        self.r: G = None
        self.txt = txt

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

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

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

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

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

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

class E:
    def __init__(self, txt: str):
        self.q: G = None
        self.s: D = None
        self.t: I = None
        self.u: I = None
        self.z: C = None
        self.w: C = None
        self.r: D = None
        self.v: D = None
        self.x: B = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.u: D = None
        self.y: I = None
        self.r: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.w: E = None
        self.o: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.p: I = None
        self.s: E = None
        self.u: B = None
        self.o: F = None
        self.r: G = None
        self.txt = txt

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

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

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