I've run the following code according to the tutorial: http://kasperdanielhansen.github.io/genbioconductor/html/SummarizedExperiment.html

library(GenomicRanges)
library(airway)
library(SummarizedExperiment)
data(airway) # loads data into R
airway
colData(airway)
airway$cell
# to know how the experiment was made:
exptData(airway)

however when runs exptData(airway) it throws the

Error: could not find function "exptData"

Could someone please tell what am I missing?