Summation of the Inverted Tangents

Geometry Level 4

$\large \sum_{m=1}^{\infty} \left [ \tan^{-1} \left (\frac{3m^2-3m+1}{m^6-3m^5+3m^4-m^3+1} \right ) \right ] = \ ?$

This is one of my original problems belonging to the set- Questions I've Made ©. Also try its sister problem