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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def copy(self, texture, source_rect=None, dest_rect=None, rotation=0, center=None, flip=lib.SDL_FLIP_NONE):
 """Copy a portion of the source texture to the current rendering target, rotating it by angle around the given center. Args: texture (Texture):
 The source texture. source_rect (Rect):
 The source rectangle, or None for the entire texture. dest_rect (Rect):
 The destination rectangle, or None for the entire rendering target. rotation (float):
 An angle in degrees that indicates the rotation that will be applied to dest_rect. center (Point):
 The point around which dest_rect will be rotated (if None, rotation will be done around dest_rect.w/2, dest_rect.h/2). flip (int):
 A value stating which flipping actions should be performed on the texture. Raises: SDLError: If an error is encountered. """

        if source_rect == None:
            source_rect_ptr = ffi.NULL
        else:
            source_rect_ptr = source_rect._ptr
            
        if dest_rect == None:
            dest_rect_ptr = ffi.NULL
        else:
            dest_rect_ptr = dest_rect._ptr

        if center == None:
            center_ptr = ffi.NULL
        else:
            center_ptr = center._ptr
            
        check_int_err(lib.SDL_RenderCopyEx(self._ptr, texture._ptr, source_rect_ptr, dest_rect_ptr, rotation, center_ptr, flip))