You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: letter_avatar.rb
    path of file: ./repos/letter_avatar/lib
    
    the code of the file until where you have to start completion: require 'open3'

require 'letter_avatar/version'
require 'letter_avatar/configuration'
require 'letter_avatar/avatar'
require 'letter_avatar/avatar_helper'
require 'letter_avatar/colors'

module LetterAvatar
  extend LetterAvatar::Configuration

  class ExecutionError < StandardError; end

  def self.setup(&_block)
    yield(self)
  end

  def sel
    
  def self.resize(from, to, width, height)
    execute(
      # NOTE: ORDER is important!
      %W(
        convert
        #{from}
        -background transparent
        -gravity center
        -thumbnail #{width}x#{height}^
        -extent #{width}x#{height}
        -unsharp 2x0.5+0.7+0
        -quality 98
        #{to}
      ).join(' ')
    )
    true
  rescue => e
    false
  end