def bin_retweet_count(retweets: float) -> str:
    """Fcn to bin retweet counts via if-else statements, rather than cut()
       function, to compare performance of computation in Class 5.

       Arguments:
           - retweets: number of retweets in millions

       Returns:
           - categorical variable grouping retweets into one of four buckets
    """
    if retweets < 10:
        retweet_cat_group = "<10"
    elif (retweets >= 10) & (retweets < 50):
        retweet_cat_group = "10-50"
    elif (retweets >= 50) & (retweets < 150):
        retweet_cat_group = "50-150"
    else:
        retweet_cat_group = "150+"

    return retweet_cat_group