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diff --git a/node_modules/date-fns/esm/differenceInISOWeekYears/index.js b/node_modules/date-fns/esm/differenceInISOWeekYears/index.js
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+import toDate from "../toDate/index.js";
+import differenceInCalendarISOWeekYears from "../differenceInCalendarISOWeekYears/index.js";
+import compareAsc from "../compareAsc/index.js";
+import subISOWeekYears from "../subISOWeekYears/index.js";
+import requiredArgs from "../_lib/requiredArgs/index.js";
+/**
+ * @name differenceInISOWeekYears
+ * @category ISO Week-Numbering Year Helpers
+ * @summary Get the number of full ISO week-numbering years between the given dates.
+ *
+ * @description
+ * Get the number of full ISO week-numbering years between the given dates.
+ *
+ * ISO week-numbering year: http://en.wikipedia.org/wiki/ISO_week_date
+ *
+ * @param {Date|Number} dateLeft - the later date
+ * @param {Date|Number} dateRight - the earlier date
+ * @returns {Number} the number of full ISO week-numbering years
+ * @throws {TypeError} 2 arguments required
+ *
+ * @example
+ * // How many full ISO week-numbering years are between 1 January 2010 and 1 January 2012?
+ * const result = differenceInISOWeekYears(
+ *   new Date(2012, 0, 1),
+ *   new Date(2010, 0, 1)
+ * )
+ * //=> 1
+ */
+export default function differenceInISOWeekYears(dirtyDateLeft, dirtyDateRight) {
+  requiredArgs(2, arguments);
+  var dateLeft = toDate(dirtyDateLeft);
+  var dateRight = toDate(dirtyDateRight);
+  var sign = compareAsc(dateLeft, dateRight);
+  var difference = Math.abs(differenceInCalendarISOWeekYears(dateLeft, dateRight));
+  dateLeft = subISOWeekYears(dateLeft, sign * difference);
+
+  // Math.abs(diff in full ISO years - diff in calendar ISO years) === 1
+  // if last calendar ISO year is not full
+  // If so, result must be decreased by 1 in absolute value
+  var isLastISOWeekYearNotFull = Number(compareAsc(dateLeft, dateRight) === -sign);
+  var result = sign * (difference - isLastISOWeekYearNotFull);
+  // Prevent negative zero
+  return result === 0 ? 0 : result;
+}
+\ No newline at end of file