将列表（格式化为字符串）反向转换为列表

Question

我有一个词典列表，它看起来像这样：

[{'T': 13472}, {'A': 13472}, {'C': 9866, 'T': 3606}, {'G': 13472}, {'G': 13472}, {'A': 221, 'C': 26, 'T': 12845, 'G': 380}, {'T': 13472}, {'A': 13472}, {'C': 546, 'T': 12926}, {'C': 13472}, {'A': 13472}, {'C': 10674, 'T': 2798}, {'C': 13472}, {'A': 13472}, {'C': 554, 'T': 12918}, {'C': 13472}, {'A': 13472}]

问题是现在，它被格式化为字符串。换句话说，当我尝试遍历列表中的项目时，我只获得单个字符。有没有办法将其转换回“词典列表”类型？

Answer 1

使用ast.literal_eval将字符串转换为python对象（安全地）：

>>> from ast import literal_eval
>>> strs = "[{'T': 13472}, {'A': 13472}, {'C': 9866, 'T': 3606}, {'G': 13472}, {'G': 13472}, {'A': 221, 'C': 26, 'T': 12845, 'G': 380}, {'T': 13472}, {'A': 13472}, {'C': 546, 'T': 12926}, {'C': 13472}, {'A': 13472}, {'C': 10674, 'T': 2798}, {'C': 13472}, {'A': 13472}, {'C': 554, 'T': 12918}, {'C': 13472}, {'A': 13472}]"
>>> literal_eval(strs)
[{'T': 13472}, {'A': 13472}, {'C': 9866, 'T': 3606}, {'G': 13472}, {'G': 13472}, {'A': 221, 'C': 26, 'T': 12845, 'G': 380}, {'T': 13472}, {'A': 13472}, {'C': 546, 'T': 12926}, {'C': 13472}, {'A': 13472}, {'C': 10674, 'T': 2798}, {'C': 13472}, {'A': 13472}, {'C': 554, 'T': 12918}, {'C': 13472}, {'A': 13472}]

Answer 2

你的意思是你有类似的东西：

x = "[{'T': 13472}, {'A': 13472}]"

然后你可以随时简单地评估它，假设源是安全的。看看：

• http://docs.python.org/2/library/functions.hatml#eval
• http://docs.python.org/2/library/ast.html#ast.literal_eval