read
Reads a klip from a klip file specified by path under given key. If such klip is not found, a value provided by source is persisted and returned instead.
Return
read klip if it exists or persisted value that was provided by source otherwise
Parameters
path
file path to retrieve and save klip for the given context
key
key to read or write the klip under in the file at path
source
a provider for a string representation to persist