code: function createPHPClass (className, baseClass, body, methods) {
  
      const baseFolder = (baseClass == 'Exchange') ? 'base/' : ''
      const baseFile =  baseFolder + baseClass + '.php'
  
      const header = [
          "<?php\n",
          "namespace ccxt;\n",
          "// PLEASE DO NOT EDIT THIS FILE, IT IS GENERATED AND WILL BE OVERWRITTEN:",
          "// https://github.com/ccxt/ccxt/blob/master/CONTRIBUTING.md#how-to-contribute-code\n",
          "use \Exception as Exception; // a common import\n",
          'class ' + className + ' extends ' + baseClass + ' {'    ,
      ]
  
      let bodyAsString = body.join ("\n")
  
      for (let method of methods) {
          const regex = new RegExp ('this->(' + method + ')\\s*\\(', 'g')
          bodyAsString = bodyAsString.replace (regex,
              (match, p1) => ('this->' + unCamelCase (p1) + ' ('))
      }
  
      const footer =[
          "}\n",
      ]
  
      const result = header.join ("\n") + "\n" + bodyAsString + "\n" + footer.join ('\n')
      return result
  }
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