def iscircular(linked_list):
    """
    Determine whether the Linked List is circular or not
    Args:
       linked_list(obj): Linked List to be checked
    Returns:
       bool: Return True if the linked list is circular, return False otherwise
    """

    if linked_list.head == None:
        return False
        
    fast = linked_list.head
    slow = linked_list.head
    
    
    while fast.next and slow.next:
        
        fast = fast.next.next
        slow = slow.next
        
        if fast == slow:
            return True
        
    
    return False