passing json list from feature and trying to catpure in steps.py

[Mark Waugh]

I have following scenario where i am passing list to a function. but i
m not able to catch that value in step.py

scenario
Then I will receive these fruits:[{"fruit1":"abc","fruit2":"def"}]

my steps looks like this

step(r'I will receive these fruits "(.*)"')
def list_fruits(step , ls):
print ls