How do we print this output?

[j.crater]

What is the error you get? Be more specific about what output you get and what output you want to have. See this and this.

Without knowing more, the only problem I see with print ("s1 is" + str((s1[0:4])) is that there is an extra closing parenthesis missing. The double parentheses around s1[0:4] are not needed though, single will do.