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

class D:
    def __init__(self, txt: str):
        self.r: D = None
        self.t: C = None
        self.o: E = None
        self.s: B = None
        self.q: B = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.z: B = None
        self.p: A = None
        self.txt = txt

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

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

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

class D:
    def __init__(self, txt: str):
        self.r: D = None
        self.t: C = None
        self.o: E = None
        self.s: B = None
        self.q: B = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.z: B = None
        self.p: A = None
        self.txt = txt

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

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

b.w = a
b.v = j
d.t = c
c.q = a
c.r = a
c.x = l
c.p = n
c.o = f
f.r = j
f.t = c
f.o = e
f.s = n
f.q = n
e.r = c
a.z = d
a.p = b
l.t = e
l.p = b
l.o = n
l.v = f
l.r = f
l.q = j
n.t = c
j.r = f
j.t = c
j.o = e
j.s = d
j.q = n
assert e.r.x.v.r.q.t.o.t.o.txt == "f"