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Two tips to help keep your documentation as professional as your code:
1. English almost never (except for -- em ("long") dashes -- for example) separates punctuation from the preceding word with a space, so colons, question-marks and exclamation points should never be preceded by whitespace.
2. It's and its are confusing because most of the time apostrophe-s ('s) means possession; this thing belongs to this thing. But in the case of "it", possession is show with just "its" -- no apostrophe. "It's" uses the apopstrophe for contraction -- "it's" is a contracted form of "it is". Whenever you're unsure, just replace the "it's" with "it is" and see if it still means what you meant for it to mean or not.
Thanks for sharing your code!