<prompt> Create an example of a regular expression that matches phone numbers from the US and Canada.  <response>: One example of a regular expression that matches phone numbers from the US and Canada is: D?d3D?D?d3D?d4This regular expression breaks down as follows:- indicates the start of the string.- D? matches zero or one non-digit character. This is used to account for any formatting character such as , , or -.- d3 matches a group of three digits, representing the area code.- Another D? is used to account for another formatting character.- d3 matches another group of three digits, representing the central office code.- Another D? is used to account for another formatting character.- d4 matches a final group of four digits, representing the subscriber number.- indicates the end of the string. 