Split a string in python
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I have python string as follows 
mystring="copy d:\Progrm Files "c:\Progrm Files\once up on a time""

how can i split this string to 

mylist=[copy,d:\Progrm Files,c:\Progrm Files\once up on a time]

When i tried to use mysring.split(" ") the spaces **Progrm Files** and **once up on a time** are also getting splitted

Please help