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SageManifold expand around infinity

Hi everyone, I am kind of new in sage and I can't find any help online.

I have written the following code on a Jupyter notebook:

M = Manifold(3, 'M', latex_name=r'\mathcal{M}')
Bc.<u,r,ph> = M.chart(r'u:(-oo,+oo) r:(0,+oo) ph:(0,2*pi):\phi') 
e = M.default_frame() 
g = M.riemannian_metric('g')
E = M.scalar_field(function('E')(u,ph), name='E')
m = M.scalar_field(function('m')(u,ph), name='m')
C = M.scalar_field(function('C')(u,ph), name='C')
Alf = M.scalar_field(function('A^l_\phi')(u,ph), name='A^l_\phi')
L = M.scalar_field(function('L')(u,ph), name='L')
f = M.scalar_field(function('f')(u,ph), name='f')
gg = M.scalar_field(function('gg')(u,ph), name='gg')
g[0,0]=2*E**2*log(r)+2*m 
g[0,1]=-1+C**2/(2*r) 
g[0,2]=8/3 * sqrt(r)*C*E+2*log(r)*E*Alf + L
g[2,2]=r**2

What I need here is to retrieve the asymptotic behavior for r->infinity of each of the metric's components, I would like to retrieve something like:

g[0,0].some_method_for_asymptotic_expansion(r, oo, order) 
RESULT: log(r) + O(1)

I tried the .series_expansion() method but it only expands around zero, and by redefining a variable like k=1/r the method arises the error

RuntimeError: ex::series(): expansion point has unknown type

Can anyone please help me? I am kind of stuck since weeks