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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def all_errors(self, joiner="; "):
 """Returns a string representation of all errors recorded for the instance."""

    parts = []
    for pname, errs in self.errors.items():
      for err in errs:
        parts.append("{0}: {1}".format(pname, err))
    return joiner.join(parts)