Compose a piece of music by integrating the assigned letter representation and provided tune.
X:1
L:1/8
M:4/4
K:Gmix
['G2 G2', 'A2 F2', 'Bgdg Bgdg', 'd4 BGBd g2 b2 BGBd bgdB AFAc', 'BGAc BGdg']  
X:1
L:1/8
M:4/4
K:Gmix
|:"_Brisk" G2 G2 (Bcdc) | TB3 A G3 c | TA3 G F2 f2 | A3 G F2 A2 | G2 G2 (Bc)(dc) | B3 A G2 c2 | 
 A2 F2 (AB)(cA) | G4 d4 :: B2 e4 (e^f) | g2 d2 (Bc)(dB) | g2 d2 (Bc)(dB) | =f2 c2 (AB)(cA) | 
 B2 d4 (e^f) | (g^f)(ed) (ed)(cB) | A2 F2 (AB)(cA) | G4 d4 | B2 G2 (Bd) g2 | B2 G2 (Bd) g2 | 
 A2 F2 (Ac) f2 | A2 F2 (Ac) f2 | B2 G2 AcBA | BdcB cedc | ^fdge dBcA | G4 d4 |] (g^f)ge Bgdg | 
 Bgdg Bgdg | =fefc Afcf | Afcf Afc^f | (g^f)gd Bgdg | Bgdg Bgdg | (fef)c AFcA | G4 d4 :: 
 BGBd g2 b2 | BGBd bgdB | AFAc =f2 a2 | AFAc afcA | BGBd gb^fa | egce dgBd | cAec BAG^F | G4 d4 :: 
 BGAc BGdg | BGAc BGdg | AFAc AFcf | AFAc AFcf | BGAB cde^f | gbag ^fedc | Bgfe dcBA | G4 d4 :|  