'rake' is not recognized as an internal or external command

Hi , 

i am using ceedling tool for unit test and code coverage i need to build this on team city while running the job it is throwing error 
 and my script file what i am trying to execute in team city 

call rake clobber
call rake gcov:all
python C:\Python36\Scripts\gcovr -e "'|^ceedling.*|^vendor.*|^build. *|^test.*|^lib.*'" --html --html-details -r . -o build\artifacts\gcov\StmUnitTestcoverage.html

env setup in tc 

please help how to fix this issue