Python中的内存高效变量类型(Memory efficient variable types in Python)

 我是python中的新手，我有两个关于内存的问题。 
 
 第一： 
 
 我可以为每个变量准确存储2位还是比int更少的内存？ 我的程序只适用于值0,1,2,3，我想节省内存。 
 
getsizeof(1)   //12 bytes
getsizeof('A') //22 bytes, but I expected 2 bytes as char :(
 
 由于2位，每个变量需要12或22个字节。 有可能在pyhton中解决这个问题吗？ 
 
 第二个类似问题： 
 
 我尝试实现树数据结构，其中每个节点有4个正确顺序的子节点。 例如理想像dict： 
 
node = {1: None, 2: None, 3: None, 4: None}
getsizeof(node) //57 bytes
 
 或者在数组中： 
 
node = [None, None, None, None]
getsizeof(node) //52 bytes, where getsizeof([]) = 36 bytes
 
 实际上，每个节点都将无用地包含36个字节。 它是~3.35Gb，有1 000 000 000个节点。 有什么方法可以节省内存吗？ 

I am completely new in python and I have two questions about memory.
 
First:
 
Can I store exactly 2 bits per variable or with less memory than int? My program works only with values 0, 1, 2, 3 and I would like to save memory.
 
getsizeof(1)   //12 bytes
getsizeof('A') //22 bytes, but I expected 2 bytes as char :(
 
Due to 2 bits, I need 12 or 22 bytes for each variable. Is possible solve this problem in pyhton?
 
Second similar problem:
 
I try to implement tree data structure, where each node have 4 children in correct order. For example ideal like dict:
 
node = {1: None, 2: None, 3: None, 4: None}
getsizeof(node) //57 bytes
 
or in array:
 
node = [None, None, None, None]
getsizeof(node) //52 bytes, where getsizeof([]) = 36 bytes
 
In fact, each node will contain 36 bytes uselessly. It is ~3.35Gb with 1 000 000 000 nodes. Is there any way to save memory?

原文：https://stackoverflow.com/questions/33248490