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Matches Russian telephone numbers in the format +7 (XXX) XXX XX-XX, where +7 is the country code for Russia. The pattern requires a 3-digit area code enclosed in parentheses, followed by groups of 3, 2, and 2 digits separated by spaces and a hyphen. With global and multiline flags, it can find multiple phone numbers across multiple lines of text, making it useful for validating or extracting formatted Russian phone numbers.