A character vector of the 20 standard amino acids in alphabetical order,
ported from Python CoNGA amino_acids.py.
Examples
AMINO_ACIDS
#> [1] "A" "C" "D" "E" "F" "G" "H" "I" "K" "L" "M" "N" "P" "Q" "R" "S" "T" "V" "W"
#> [20] "Y"
length(AMINO_ACIDS) # 20
#> [1] 20