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: zammad.rb
    path of file: ./repos/zammad/lib/service/image
    
    the code of the file until where you have to start completion: # Copyright (C) 2012-2024 Zammad Foundation, https://zammad-foundation.org/

class Service::Image::Zammad

  API_HOST      = 'https://images.zammad.com'.freeze
  OPEN_TIMEOUT  = 4
  READ_TIMEOUT  = 6
  TOTAL_TIMEOUT = 6
  DISABLE_IN_TEST_ENV = true

  def self.user(email)
    raise Exceptions::UnprocessableEnti
    
  def self.user(email)
    raise Exceptions::UnprocessableEntity, 'no email given' if email.blank?

    return if Rails.env.test? && DISABLE_IN_TEST_ENV

    email.downcase!

    return if email.match?(%r{@example.com$})

    # fetch image
    response = UserAgent.post(
      "#{API_HOST}/api/v1/person/image",
      {
        email: email,
      },
      {
        open_timeout:  OPEN_TIMEOUT,
        read_timeout:  READ_TIMEOUT,
        total_timeout: TOTAL_TIMEOUT,
        verify_ssl:    true,
      },
    )
    if !response.success?
      Rails.logger.info "Can't fetch image for '#{email}' (maybe no avatar available), http code: #{response.code}"
      return
    end