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  3. Python Data Science Toolbox (Part 1)

Exercise

Bringing it all together (1)

This is awesome! You have now learned how to write anonymous functions using lambda, how to pass lambda functions as arguments to other functions such as map(), filter(), and reduce(), as well as how to write errors and output custom error messages within your functions. You will now put together these learnings to good use by working with a Twitter dataset. Before practicing your new error handling skills; in this exercise, you will write a lambda function and use filter() to select retweets, that is, tweets that begin with the string 'RT'.

To help you accomplish this, the Twitter data has been imported into the DataFrame, tweets_df. Go for it!

Instructions

100 XP
  • In the filter() call, pass a lambda function and the sequence of tweets as strings, tweets_df['text']. The lambda function should check if the first 2 characters in a tweet x are 'RT'. Assign the resulting filter object to result. To get the first 2 characters in a tweet x, use x[0:2]. To check equality, use a Boolean filter with ==.
  • Convert result to a list and print out the list.