By Ismail Shakil and Anna Mehler Paperny OTTAWA (Reuters) -Canada’s government introduced legislation Monday to implement a “national freeze” on the sale and purchase of handguns as part of a gun control package that would also limit magazine capacities and ban some toys that look like guns. The new legislation, which resurrects some measures that were shelved last year amid a national election, comes just a week after a gunman killed 19 children and two teachers in their classroom in Uvalde, Texas. Prime Minister Justin Trudeau told reporters the new measures were needed as gun violence was i…