R

 no claim that any of this is original code
# lifted in learning exercises over time
# the RStudio editor will code fold the examples below

# Read Excel, Manipulate Rows/Columns, Write Excel ------------------------------------------------

library(dplyr)
library(readxl)
library(writexl)
library(lubridate)
library(stringr)

XLSX_FILE <- "Planets"

planets <- read_excel(paste0(XLSX_FILE,".xlsx"), sheet = "List of Planets")

# add a column with the row number
planets <- mutate(planets, RowNum = row_number())

# move RowNum column to the far left
planets <- select(planets, RowNum, everything())

# rename a column
names(planets)[names(planets) == 'RowNum'] <- 'Row Number'

# a good way to rename lots of columns
# omitting a column will remove it
planets <- rename(planets,
                  RowNum = "Row Number",
                  Planet = Planet,
                  Distance = "Distance (AU)",
                  Revolution = Revolution,
                  Rotation = Rotation,
                  Mass = Mass,
                  Diameter = Diameter,
                  Satellites = Satellites)

# remove RowNum column
planets <- subset(planets, select = -c(RowNum))

# remove the Uranus row
planets <- filter(planets, Planet != "Uranus")

# getting and setting a valume in a dataframe
saturn_mass <- as.numeric(planets[which(planets$Planet == "Saturn"), "Mass"])
planets[which(planets$Planet == "Saturn"), "Mass"] <- saturn_mass

# create Excel filename with date/time stamp at the end
filename <- paste(XLSX_FILE, now())
# remove the seconds and replace the colon in now()
filename <- str_sub(str_replace_all(filename,":",""),-100,-3)
filename <- paste0(filename,".xlsx")

# can save multiple worksheets
worksheets <- list("List of Planets" = planets,
                   "Copy of List of Planets" = planets)
tmp <- writexl::write_xlsx(worksheets, filename)