def to_sci_string(number):
mant, exp = peng.functions._to_eng_tuple(number)<EOL>return "<STR_LIT>".format(<EOL>mant=mant, exp_sign="<STR_LIT:->" if exp < <NUM_LIT:0> else "<STR_LIT:+>", exp=abs(exp)<EOL>)<EOL>
Return string with the number formatted in scientific notation.

This function does not have all the configurability of the public function
to_scientific_string, it is a convenience function to test _to_eng_tuple