Create a musical composition adhering to the provided thematic and alphabetical guidelines.
X:1
L:1/8
M:4/4
K:Bb
['f edcA BF B2 dfga bfdB e2', 'B f bBaB gBfB dfga bfdB cf=ef']  
X:1
L:1/8
M:4/4
K:Bb
 f | edcA BF B2 | dfga bfdB | e2 d=B cG c2 | cdef gedc | Bc/d/ BFBF B2 | Bcde fbdB | Egfe dfdB | 
 FBAc B2 B || f | bBaB gBfB | dfga bfdB | cf=ef dfef | dbag f=edc | d<B c/B/A/B/ F<B c/B/A/B/ | 
 GBFB EBDB | Egfe dfdB | FBAc B2 B ||  