class A:
    def __init__(self, txt: str):
        self.s: F = None
        self.r: F = None
        self.z: E = None
        self.y: D = None
        self.q: D = None
        self.o: E = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.o: D = None
        self.x: F = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.y: G = None
        self.z: C = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.q: F = None
        self.x: B = None
        self.w: D = None
        self.t: G = None
        self.y: E = None
        self.p: A = None
        self.txt = txt

h = A("h")
j = B("j")
a = C("a")
n = D("n")
c = E("c")
f = F("f")
d = G("d")
i = G("i")
g = G("g")
b = E("b")

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

class B:
    def __init__(self, txt: str):
        self.o: D = None
        self.x: F = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.y: G = None
        self.z: C = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.q: F = None
        self.x: B = None
        self.w: D = None
        self.t: G = None
        self.y: E = None
        self.p: A = None
        self.txt = txt

h = A("h")
j = B("j")
a = C("a")
n = D("n")
c = E("c")
f = F("f")
d = G("d")
i = G("i")
g = G("g")
b = E("b")

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