What is the test for determining whether a default was caused by an attorney's mistake, inadvertence, surprise or neglect?

"The court's determination of whether the default was caused by the attorney's mistake, inadvertence, surprise, or neglect is in part a credibility determination. [Citation.]" (Cowan v. Krayzman (2011) 196 Cal.App.4th 907, 915.) "'Credibility is an issue for the fact finder . . . we do not reweigh evidence or reassess the credibility of witnesses[.]'" (Ibid.) "'When . . . 'the evidence gives rise to conflicting reasonable inferences, one of which supports the findings of the trial court, the trial court's finding is conclusive on appeal[.]' [Citation.]'" (Ibid.)

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