Add Python solution to challenge 059

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diff --git a/challenge-059/paulo-custodio/python/ch-1.py b/challenge-059/paulo-custodio/python/ch-1.py
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+#!/usr/bin/env python3
+
+# Challenge 059
+#
+# TASK #1 › Linked List
+# Reviewed by Ryan Thompson
+# You are given a linked list and a value k. Write a script to partition the
+# linked list such that all nodes less than k come before nodes greater than or
+# equal to k. Make sure you preserve the original relative order of the nodes in
+# each of the two partitions.
+#
+# For example:
+#
+# Linked List: 1 -> 4 -> 3 -> 2 -> 5 -> 2
+#
+# k = 3
+#
+# Expected Output: 1 -> 2 -> 2 -> 4 -> 3 -> 5.
+
+import sys
+
+class Node:
+    def __init__(self, data):
+        self.data = data
+        self.next = None
+
+    def __str__(self):
+        out = "["+str(self.data)
+        if self.next:
+            return out+","+str(self.next)+"]"
+        else:
+            return out+"]"
+
+class LinkedList:
+    def __init__(self):
+        self.head = None
+
+    def __str__(self):
+        out = ""
+        current = self.head
+        while current:
+            out += str(current.data)+" -> "
+            current = current.next
+        out += "None"
+        return out
+
+    def push_front(self, data):
+        new_node = Node(data)
+        new_node.next = self.head
+        self.head = new_node
+
+    def push_back(self, data):
+        new_node = Node(data)
+        if not self.head:
+            self.head = new_node
+        else:
+            last_node = self.head
+            while last_node.next:
+                last_node = last_node.next
+            last_node.next = new_node
+
+    def insert_at(self, index, data):
+        if index == 0:
+            self.push_front(data)
+        else:
+            new_node = Node(data)
+            current = self.head
+            for _ in range(index - 1):
+                if not current:
+                    raise IndexError("Index out of bounds")
+                current = current.next
+            new_node.next = current.next
+            current.next = new_node
+
+    def remove_node(self, key):
+        current = self.head
+        if current and current.data == key:
+            self.head = current.next
+            current = None
+        else:
+            prev = None
+            while current and current.data != key:
+                prev = current
+                current = current.next
+            if current:
+                prev.next = current.next
+                current = None
+
+def partition(list, k):
+    below = LinkedList()
+    above = LinkedList()
+
+    p = list.head
+    while p:
+        if p.data < k:
+            below.push_back(p.data)
+        else:
+            above.push_back(p.data)
+        p = p.next
+
+    list = below
+    p = above.head
+    while p:
+        list.push_back(p.data)
+        p = p.next
+
+    return list
+
+k = int(sys.argv[1])
+list = LinkedList()
+for x in sys.argv[2:]:
+    list.push_back(int(x))
+list = partition(list, k)
+print(list)