                  fail: @escaping FailBlock) -> URLSessionTask?
 }
 
+let JSONMIMEType = "application/json"
+
 extension Biceps {
     open func requestJSON() {
-        if let combinedRequest = self.combinedRequest, combinedRequest.count > 0 {
-            for biceps in combinedRequest {
-                biceps.requestJSON()
-            }
-        } else {
-            request(for: self.internalType, contentType: "")
-        }
+        request(for: self.internalType, contentType: JSONMIMEType)
     }
     
     var requester: BicepsRequestable {

        
        return biceps
    }
    
    open func configuration(_ block: (BicepsConfiguration) -> Void) -> Biceps {
        block(self.configuration)
        return self


// MARK: Biceps Errors
public enum BicepsError: Error {
    public enum UnimplementedMethodError: Error {
        case fetch
        case send
    }
    
    public enum DependencyError: Error {
        case cycle
    }
}

extension BicepsError.UnimplementedMethodError: CustomStringConvertible {
    public var description: String {
        switch self {
        case .fetch: return "BicepsUnimplementMethodError: not implement fetch method"
