class A:
    def __init__(self, txt: str):
        self.t: B = None
        self.o: G = None
        self.v: D = None
        self.r: F = None
        self.txt = txt

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

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

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

class E:
    def __init__(self, txt: str):
        self.x: C = None
        self.z: B = None
        self.v: A = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.t: C = None
        self.s: I = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.t: A = None
        self.s: B = None
        self.w: D = None
        self.v: I = None
        self.r: D = None
        self.o: C = None
        self.txt = txt

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

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

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

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

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

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

class E:
    def __init__(self, txt: str):
        self.x: C = None
        self.z: B = None
        self.v: A = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.t: C = None
        self.s: I = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.t: A = None
        self.s: B = None
        self.w: D = None
        self.v: I = None
        self.r: D = None
        self.o: C = None
        self.txt = txt

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

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

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