Under Python 2.6, curly braces in strings to `.format()` MUST be indexed.

Double to single quotes and minor formatting.
Under Python 2.6, curly braces in strings to `.format()` MUST be indexed.
Under Python 2.6, curly braces in strings to `.format()` MUST be indexed.
Under Python 2.6, curly braces in strings to `.format()` MUST be indexed.
Under Python 2.6, curly braces in strings to `.format()` MUST be indexed.
Under Python 2.6, curly braces in strings to `.format()` MUST be indexed.
Under Python 2.6, curly braces in strings to `.format()` MUST be indexed.
Under Python 2.6, curly braces in strings to `.format()` MUST be indexed.
Under Python 2.6, curly braces in strings to `.format()` MUST be indexed.
Under Python 2.6, curly braces in strings to `.format()` MUST be indexed.

Less local variables.
Merge pull request #8395 from s0undt3ch/hotfix/string-format-no-index

Force indexes in string format calls