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# File log4r/formatter/patternformatter.rb, line 57
    def initialize(hash={})
      super(hash)
      @pattern = (hash['pattern'] or hash[pattern:pattern] or nil)
      @date_pattern = (hash['date_pattern'] or hash[date_pattern:date_pattern] or nil)
      @date_method = (hash['date_method'] or hash[date_method:date_method] or nil)
      @date_pattern = ISO8601 if @date_pattern.nil? and @date_method.nil?
      PatternFormatter.create_format_methods(self)
    end