class Faraday::ProxyOptions

configuration used when making an HTTP request.
ProxyOptions contains the configurable properties for the proxy

def self.from(value) 

def self.from(value)
  case value
  when String
    # URIs without a scheme should default to http (like 'example:123').
    # This fixes #1282 and prevents a silent failure in some adapters.
    value = "http://#{value}" unless value.include?('://')
    value = { uri: Utils.URI(value) }
  when URI
    value = { uri: value }
  when Hash, Options
    if (uri = value.delete(:uri))
      value[:uri] = Utils.URI(uri)
    end
  end
  super(value)
end