What you're using in the python code is called a list in python, and it's tottaly different from R vectors, if i get what you wanna do:
# you can do like this if you'll put them manually
v <- c("a", "b", "c")
# if your values are in a list
v <- as.vector(your_list)
# if you just need to append
v <- append(v, value, after=length(v))