Im 99.99999% sure this is right as i have been told by many experienced players that have also seen Deep Purple them selves play it like this 
 
 
Standard Tuning :E  B  G  D  A  E 
 
 
E|-------------------------------------------------| 
B|-0--3--5----0--3--6-5--3--0----0--3--5--3--0-----| 
G|-0--3--5----0--3--6-5--3--0----0--3--5--3--0-----| 
D|-------------------------------------------------| 
A|-------------------------------------------------| 
E|-------------------------------------------------| 
 
Thats the main Riff 
 
E|----------------------| 
B|----------------------| 
G|----------------------| 
D|-5--5--5--5-----------| 
A|-7--7--7--7--5--5--4--| 
E|-------------7--7--6--| 
 
E|--------------------------------------| 
B|--------------------------------------| 
G|--------------------------------------| 
D|--------------------------------------| 
A|-4--4--4--4--4--4----4--4--4--4--4--4-| 
E|-4--4--6--4--6--4----4--4--6--4--6--4-| 
 
Then somewhere after (i cant really remember where abouts it comes) but that play that but im afraid thats all i can remember i will update when i can actually remember/find out how the rest goes 
 
 
QUALITY 
 
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