Hi Rizwan,
You can also try creating the symbol from a text file. Within Symbol Editor, you can go to File > Generate Symbol from Pins and select the appropriate file. I have made an Excel template (attached) for simplifying this process - enter in the symbol data and save the worksheet in .CSV format, then import this into Symbol Editor. This makes it easy to read a datasheet and generate the necessary pins quickly - later you can fine-tune the symbol's appearance.