I want to add three new functions to the the custom function extension

functions/INVERSE_METRIX.gs

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+// @author Nwachukwu Ujubuonu https://github.com/Hemephelus/google-sheets-custom-function
+/**
+ * Returns the inverse of a square metrix.
+ * 
+ * @param {C1:D2} range The square metrix to invert.
+ *
+ * @return the inverse of a square metrix.
+ * @customfunction
+ */  
+function INVERSE_METRIX(range) {
+
+  if(range[i].length !== range.length)return 'this is not a square metrix'
+
+  var temp,
+    N = range.length,
+    E = [];
+
+  for (var i = 0; i < N; i++)
+
+    E[i] = [];
+
+  for (i = 0; i < N; i++)
+
+    for (var j = 0; j < N; j++) {
+
+      E[i][j] = 0;
+      if (i == j)
+        E[i][j] = 1;
+
+    }
+
+  for (var k = 0; k < N; k++) {
+
+    temp = range[k][k];
+
+    for (var j = 0; j < N; j++) {
+
+      range[k][j] /= temp;
+      E[k][j] /= temp;
+    }
+
+    for (var i = k + 1; i < N; i++) {
+
+      temp = range[i][k];
+
+      for (var j = 0; j < N; j++) {
+
+        range[i][j] -= range[k][j] * temp;
+        E[i][j] -= E[k][j] * temp;
+
+      }
+
+    }
+
+  }
+
+  for (var k = N - 1; k > 0; k--) {
+
+    for (var i = k - 1; i >= 0; i--) {
+
+      temp = range[i][k];
+
+      for (var j = 0; j < N; j++) {
+
+        range[i][j] -= range[k][j] * temp;
+        E[i][j] -= E[k][j] * temp;
+
+      }
+
+    }
+
+  }
+
+  for (var i = 0; i < N; i++)
+
+    for (var j = 0; j < N; j++)
+
+      range[i][j] = E[i][j];
+  return range;
+
+}

functions/ROMAN_TO_NUMBER.gs

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+// @author Nwachukwu Ujubuonu https://github.com/Hemephelus/google-sheets-custom-function
+/**
+ * Returns the values of the Roman Text as an Integer.
+ * 
+ * @param {A2:A9 or "XXIII"} range The roman text to convert.
+ *
+ * @return the values of the Roman Text as an Integer.
+ * @customfunction
+ */  
+function ROMAN_TO_NUMBER(range) {
+
+  let array = []
+
+  if(!Array.isArray(range))return ROM_TO_NUM_(range)
+
+
+  for (let i = 0; i < range.length; i++) {
+
+    array.push([ROM_TO_NUM_(range[i][0])] )
+
+  }
+  return array
+};
+
+function ROM_TO_NUM_(roman_text) {
+
+    let singleLetters = {
+    "I": 1,
+    "V": 5,
+    "X": 10,
+    "L": 50,
+    "C": 100,
+    "D": 500,
+    "M": 1000,
+  }
+
+
+  let total = 0
+  let val = 0
+
+  for (let i = 0; i < roman_text.length; i++) {
+
+    if (singleLetters[roman_text[i]] < singleLetters[roman_text[i + 1]]) {
+
+      val = singleLetters[roman_text[i + 1]] - singleLetters[roman_text[i]]
+      total += val
+      i++
+
+    } else {
+
+      total += singleLetters[roman_text[i]]
+
+    }
+
+  }
+  return total
+};

functions/SUPER_UNIQUE.gs

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+// @author Nwachukwu Ujubuonu https://github.com/Hemephelus/google-sheets-custom-function
+/**
+ * Returns unique rows in the provided source range and selected columns, discarding duplicates. Rows are returned in the order in which they first appear in the source range. 
+ * 
+ * @param {C1:D2} range The data to filter by unique entries.
+ * @param {"1,2"} cols The columns you want to filter by.
+ *
+ * @return Unique rows in the provided source range and selected columns.
+ * @customfunction
+ */ 
+function SUPER_UNIQUE(range,cols) {
+  cols = cols.replace(" ","").split(',')
+  let newRange = {}
+
+  for(let i = 0; i < range.length; i++){
+    let subRange = ''
+    for(let j = 0; j < cols.length; j++){
+      subRange = subRange+range[i][cols[j]-1]
+    }
+     newRange[subRange] = range[i]
+
+  }
+
+ return Object.values(newRange)
+
+
+}