Challenge 13: Onsite and Online Transactions Level: Medium Description: Your company keeps data related to online and onsite transactions in a tabular dataset with the following format: Index Online Onsite 1 A.6777-01 2 7736-01 3 L-2210341175-00-000020 4 L-3210341175-00-000020 5 F5454 6 B_7736-01-00-000020 7 F5454 7736-01 In this challenge, you are asked to extract digits from the transactions (which are related to the bought products) given the following guidelines: (1) if the onsite transaction starts with “L”, then take its first 12 digits; otherwise, take its first 6 digits; and (2) if the onsite transaction has a missing value, then take the string from the online transaction.