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: market.rb
    path of file: ./repos/cryptoexchange/lib/cryptoexchange/exchanges/waves
    
    the code of the file until where you have to start completion: module Cryptoexchange::Exchanges
  module Waves
    class Market < Cryptoexchange::Models::Market
      NAME    = 'waves'
      API_URL = 'https://api.wavesplatform.com/v0'
      TOKEN_URL = 'https://api.wavesplatform.com/v0/assets?ticker=*'


      class << self
        def fetch_symbol
          Cryptoexchange::Cache.ticker_cache.fetch(TOKEN_URL) do
            begin
              fetch_response = http_get(TOKEN_URL)
              if fetch_response.code == 200
                result  = JSON.parse(fetch_response)["data"]
                symbols = {}
                result.map do |symbol|
                  symbol = symbol["data"]
                  symbols[symbol['id']] = symbol['ticker']
                end
                symbols
              elsif fetch_response.code == 400
                raise Cryptoexchange::HttpBadRequestError, { response: fetch_response }
 
    
        def fetch_symbol
          Cryptoexchange::Cache.ticker_cache.fetch(TOKEN_URL) do
            begin
              fetch_response = http_get(TOKEN_URL)
              if fetch_response.code == 200
                result  = JSON.parse(fetch_response)["data"]
                symbols = {}
                result.map do |symbol|
                  symbol = symbol["data"]
                  symbols[symbol['id']] = symbol['ticker']
                end
                symbols
              elsif fetch_response.code == 400
                raise Cryptoexchange::HttpBadRequestError, { response: fetch_response }
              else
                raise Cryptoexchange::HttpResponseError, { response: fetch_response }
              end
            rescue HTTP::ConnectionError => e
              raise Cryptoexchange::HttpConnectionError, { error: e, response: fetch_response }
            rescue HTTP::TimeoutError => e
              raise Cryptoexchange::HttpTimeoutError, { error: e, response: fetch_response }
            rescue JSON::ParserError => e
              raise Cryptoexchange::JsonParseError, { error: e, response: fetch_response }
            rescue TypeError => e
              raise Cryptoexchange::TypeFormatError, { error: e, response: fetch_response }
            end