I downloaded executable file of tesseract-OCR and installed it. On the other hand, I also downloaded a zipfile of leptonica from http://www.leptonica.com/download.html. It i
I know it is too late for you but it might help others.
Installation of leptonica will not be a complete solution at all in order to remove error while installing tesseract-ocr. After the installation of tesseract using windows installer available here, you should install the python wrapper as:
pip install pytesseract
Last but not least, you should also set the tesseract path in your script after importing pytesseract library as below (Please do not forget that installation path might be modified in your case!):
pytesseract.pytesseract.tesseract_cmd = r'C:\Program Files (x86)\Tesseract-OCR\tesseract.exe'