LeetCode with Python -> Linked List

# Definition for singly-linked list.
# class ListNode(object):
#     def __init__(self, x):
#         self.val = x
#         self.next = None

class Solution(object):
    def hasCycle(self, head):
        """
        :type head: ListNode
        :rtype: bool
        """
        while head.next is not None:
            if head.value is None:
                return True
            head.value = None
            head =  head.next
        return Faulse