Editing Data frames in R and formatting

I was wondering how I can edit my data frame. I have a data frame like the one below.

   ID    Value
  A1_5    5.6
  A2_7    3.4
  A3_8    6.7 

I want to duplicate the IDs by changing the first letter, and repeating the same value since they are coming from the same samples. So I want to create a data frame such as…

   ID    Value
  A1_5    5.6
  B1_5    5.6
  A2_7    3.4
  B2_7    3.4
  A3_8    6.7 
  B3_8    6.7 

How can I go about doing this?

Thank you in advance.

>Solution :

library(dplyr)
data %>%
    mutate(
        ID = stringr::str_replace(ID, 'A', 'B')
    ) %>%
    bind_rows(data)