Python 3.7

For each informal pattern description or set of strings below, define a regular expression that fits the patterns description or matches all the strings in the set and no other.

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11.8 For each informal pattern description or set of strings below, define a regular expres sion that fits the pattern description or matches all the strings in the set and no other. (a) Strings containing an apostrophe (') (b) Any sequence of three lowercase letters in the alphabet (c) The string representation of a positive integer (d) The string representation of a nonnegative integer (e) The string representation of a negative integer (f) The string representation of an integer (whether positive or not) (g) The string representation of a floating-point value using the decimal point notation