Try to fix issue331

[lyl1999]

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Description of Changes

Try to fix issue 331, adding a function to set default locale

[jadchaar]

Hi @lyl1999, the solution to 331 needs to be a bit more robust. It needs to set the default locale on the module level so that every single call to an arrow function uses that locale (e.g. parsing, humanize, formatting). If you'd like to take this on, feel free to re-open this PR and attempt the more robust solution I describe above.