blocks|key|3011590|text|JSON+syntax不是Python语法。JSON要求其字符串使用双引号。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|3011591|entityMap|0|LINK|mutability|MUTABLE|url|http://www.json.org/^0|0|B|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@$A|M|B|N|1|O]]|C|$]]|$1|D|3|-4|5|6|7|P|8|@]|9|@]|C|$]]]|E|$F|$5|G|H|I|C|$J|K]]]]

<a href="http://www.json.org/" rel="noreferrer">JSON syntax</a> is not Python syntax. JSON requires double quotes for its strings.

blocks|key|3225673|text|您可以通过以下方式使用双引号转储JSON：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3225674|import+json

#+mixing+single+and+double+quotes
data+=+{'jsonKey':+'jsonValue',"title":+"hello+world"}

#+get+string+with+all+double+quotes
json_string+=+json.dumps(data)+|code-block|syntax|javascript|3225675|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

You can dump JSON with double quote by: 

<pre><code>import json

# mixing single and double quotes
data = {'jsonKey': 'jsonValue',"title": "hello world"}

# get string with all double quotes
json_string = json.dumps(data) 
</code></pre>

blocks|key|3011608|text|您可以使用ast.literal_eval()|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|3011609|>>>+import+ast
>>>+s+=+"{'username':'dfdsfdsf'}"
>>>+ast.literal_eval(s)
{'username':+'dfdsfdsf'}|code-block|syntax|javascript|3011610|entityMap^0|5|I|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|P|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Q|8|@]|D|@]|E|$]]]|L|$]]

you can use <code>ast.literal_eval()</code>

<pre><code>&gt;&gt;&gt; import ast
&gt;&gt;&gt; s = "{'username':'dfdsfdsf'}"
&gt;&gt;&gt; ast.literal_eval(s)
{'username': 'dfdsfdsf'}
</code></pre>

blocks|key|292101|text|demjson也是一个很好的包，可以解决json语法不好的问题：|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|292102|pip+install+demjson|code-block|syntax|javascript|292103|使用：|style|BOLD|292104|from+demjson+import+decode
bad_json+=+"{'username':'dfdsfdsf'}"
python_dict+=+decode(bad_json)|292105|编辑：|292106|292107|+demjson.decode是处理损坏的json的一个很好的工具，但是当你处理大量的json数据时，ast.literal_eval是一个更好的匹配，而且速度更快。|blockquote|CODE|292108|292109|entityMap|0|LINK|mutability|MUTABLE|url|https://pypi.org/project/demjson/^0|0|7|0|0|0|0|3|0|0|0|3|0|0|1|E|1F|G|0|0^^$0|@$1|2|3|4|5|6|7|14|8|@]|9|@$A|15|B|16|1|17]]|C|$]]|$1|D|3|E|5|F|7|18|8|@]|9|@]|C|$G|H]]|$1|I|3|J|5|6|7|19|8|@$A|1A|B|1B|K|L]]|9|@]|C|$]]|$1|M|3|N|5|F|7|1C|8|@]|9|@]|C|$G|H]]|$1|O|3|P|5|6|7|1D|8|@$A|1E|B|1F|K|L]]|9|@]|C|$]]|$1|Q|3|-4|5|6|7|1G|8|@]|9|@]|C|$]]|$1|R|3|S|5|T|7|1H|8|@$A|1I|B|1J|K|U]|$A|1K|B|1L|K|U]]|9|@]|C|$]]|$1|V|3|-4|5|6|7|1M|8|@]|9|@]|C|$]]|$1|W|3|-4|5|6|7|1N|8|@]|9|@]|C|$]]]|X|$Y|$5|Z|10|11|C|$12|13]]]]

<a href="https://pypi.org/project/demjson/" rel="noreferrer">demjson</a> is also a good package to solve the problem of bad json syntax:
<pre><code>pip install demjson
</code></pre>
Usage:
<pre><code>from demjson import decode
bad_json = &quot;{'username':'dfdsfdsf'}&quot;
python_dict = decode(bad_json)
</code></pre>
Edit:
<blockquote>
<code>demjson.decode</code> is a great tool for damaged json, but when you are dealing with big amourt of json data <code>ast.literal_eval</code> is a better match and much faster.
</blockquote>

blocks|key|3011627|text|import+json
data+=+json.dumps(list)
print(data)|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|3011628|上面的代码片段应该可以工作。|unstyled|3011629|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|J|8|@]|9|@]|A|$]]|$1|G|3|-4|5|F|7|K|8|@]|9|@]|A|$]]]|H|$]]

<pre><code>import json
data = json.dumps(list)
print(data)
</code></pre>

The above code snippet should work.

blocks|key|289346|text|如上所述，JSON不是Python语法。在JSON中需要使用双引号。它的创建者以使用严格的允许语法子集来缓解程序员的认知过载而闻名。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|289347|289348|正如@Jiaaro指出的那样，如果其中一个字符串本身包含单引号，则下面的JSON可能会失败。不要使用。此处仅作为不起作用的示例。|offset|length|style|BOLD|289349|知道JSON字符串中没有单引号是非常有用的。比方说，你从浏览器控制台复制并粘贴了它。然后，您只需输入|289350|a+=+json.loads('very_long_json_string_pasted_here')|code-block|syntax|javascript|289351|否则，如果它使用单引号，也可能会中断。|289352|entityMap^0|0|0|L|17|0|0|0|0^^$0|@$1|2|3|4|5|6|7|T|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|U|8|@]|9|@]|A|$]]|$1|C|3|D|5|6|7|V|8|@$E|W|F|X|G|H]]|9|@]|A|$]]|$1|I|3|J|5|6|7|Y|8|@]|9|@]|A|$]]|$1|K|3|L|5|M|7|Z|8|@]|9|@]|A|$N|O]]|$1|P|3|Q|5|6|7|10|8|@]|9|@]|A|$]]|$1|R|3|-4|5|6|7|11|8|@]|9|@]|A|$]]]|S|$]]

As said, JSON is not Python syntax. You need to use double quotes in JSON. Its creator is (in-)famous for using strict subsets of allowable syntax to ease programmer cognitive overload.

<hr>

Below can fail if one of the JSON strings itself contains a single quote as pointed out by @Jiaaro. DO NOT USE. Left here as an example of what does not work.

It is really useful to know that there are no single quotes in a JSON string. Say, you copied and pasted it from a browser console/whatever. Then, you can just type

<pre><code>a = json.loads('very_long_json_string_pasted_here')
</code></pre>

This might otherwise break if it used single quotes, too.

blocks|key|3011687|text|我最近遇到了一个非常类似的问题，我相信我的解决方案也适用于您。我有一个文本文件，其中包含表单中的项目列表：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3011688|["first+item",+'the+"Second"+item',+"thi'rd",+'some+\\"hellish\\"+\'quoted"+item']|code-block|syntax|javascript|3011689|我想把上面的代码解析成一个python列表，但我对eval()并不热衷，因为我不能信任输入。我首先尝试使用JSON，但它只接受双引号的项目，所以我为这个特定的情况编写了我自己的非常简单的lexer+(只需插入您自己的“字符串”，您将得到输出列表：'+items+')|3011690|#This+lexer+takes+a+JSON-like+'array'+string+and+converts+single-quoted+array+items+into+escaped+double-quoted+items,
#then+puts+the+'array'+into+a+python+list
#Issues+such+as++["item+1",+'","item+2+including+those+double+quotes":"',+"item+3"]+are+resolved+with+this+lexer
items+=+[]++++++#List+of+lexed+items
item+=+""+++++++#Current+item+container
dq+=+True+++++++#Double-quotes+active+(False->single+quotes+active)
bs+=+0++++++++++#backslash+counter
in_item+=+False+#True+if+currently+lexing+an+item+within+the+quotes+(False+if+outside+the+quotes;+ie+comma+and+whitespace)
for+c+in+stringtoparse[1:-1]:+++#Assuming+encasement+by+brackets
++++if+c=="\\":+#if+there+are+backslashes,+count+them!+Odd+numbers+escape+the+quotes...
++++++++bs+=+bs+%2B+1
++++++++continue++++++++++++++++++++
++++if+(dq+and+c=='"')+or+(not+dq+and+c=="'"):++#quote+matched+at+start/end+of+an+item
++++++++if+bs+&+1==1:+++#if+escaped+quote,+ignore+as+it+must+be+part+of+the+item
++++++++++++continue
++++++++else:+++#not+escaped+quote+-+toggle+in_item
++++++++++++in_item+=+not+in_item
++++++++++++if+item!="":++++++++++++#if+item+not+empty,+we+must+be+at+the+end
++++++++++++++++items+%2B=+[item]+++++#so+add+it+to+the+list+of+items
++++++++++++++++item+=+""+++++++++++#and+reset+for+the+next+item
++++++++++++continue++++++++++++++++
++++if+not+in_item:+#toggle+of+single/double+quotes+to+enclose+items
++++++++if+dq+and+c=="'":
++++++++++++dq+=+False
++++++++++++in_item+=+True
++++++++elif+not+dq+and+c=='"':
++++++++++++dq+=+True
++++++++++++in_item+=+True
++++++++continue
++++if+in_item:+#character+is+part+of+an+item,+append+it+to+the+item
++++++++if+not+dq+and+c=='"':+++++++++++#if+we+are+using+single+quotes
++++++++++++item+%2B=+bs+*+"\\"+%2B+"\""++++#escape+double+quotes+for+JSON
++++++++else:
++++++++++++item+%2B=+bs+*+"\\"+%2B+c
++++++++bs+=+0
++++++++continue|3011691|希望它对某些人有用。享受吧！|3011692|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|S|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

I recently came up against a very similar problem, and believe my solution would work for you too. I had a text file which contained a list of items in the form:

<pre><code>["first item", 'the "Second" item', "thi'rd", 'some \\"hellish\\" \'quoted" item']
</code></pre>

I wanted to parse the above into a python list but was not keen on eval() as I couldn't trust the input. I tried first using JSON but it only accepts double quoted items, so I wrote my own very simple lexer for this specific case (just plug in your own "stringtoparse" and you will get as output list: 'items')

<pre><code>#This lexer takes a JSON-like 'array' string and converts single-quoted array items into escaped double-quoted items,
#then puts the 'array' into a python list
#Issues such as ["item 1", '","item 2 including those double quotes":"', "item 3"] are resolved with this lexer
items = [] #List of lexed items
item = "" #Current item container
dq = True #Double-quotes active (False-&gt;single quotes active)
bs = 0 #backslash counter
in_item = False #True if currently lexing an item within the quotes (False if outside the quotes; ie comma and whitespace)
for c in stringtoparse[1:-1]: #Assuming encasement by brackets
 if c=="\\": #if there are backslashes, count them! Odd numbers escape the quotes...
 bs = bs + 1
 continue 
 if (dq and c=='"') or (not dq and c=="'"): #quote matched at start/end of an item
 if bs &amp; 1==1: #if escaped quote, ignore as it must be part of the item
 continue
 else: #not escaped quote - toggle in_item
 in_item = not in_item
 if item!="": #if item not empty, we must be at the end
 items += [item] #so add it to the list of items
 item = "" #and reset for the next item
 continue 
 if not in_item: #toggle of single/double quotes to enclose items
 if dq and c=="'":
 dq = False
 in_item = True
 elif not dq and c=='"':
 dq = True
 in_item = True
 continue
 if in_item: #character is part of an item, append it to the item
 if not dq and c=='"': #if we are using single quotes
 item += bs * "\\" + "\"" #escape double quotes for JSON
 else:
 item += bs * "\\" + c
 bs = 0
 continue
</code></pre>

Hopefully it is useful to somebody. Enjoy!

blocks|key|294371|text|import+ast+
answer+=+subprocess.check_output(PYTHON_+%2B+command,+shell=True).strip()
++++print(ast.literal_eval(answer.decode(UTF_)))|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|294372|对我很管用|unstyled|294373|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|J|8|@]|9|@]|A|$]]|$1|G|3|-4|5|F|7|K|8|@]|9|@]|A|$]]]|H|$]]

<pre><code>import ast 
answer = subprocess.check_output(PYTHON_ + command, shell=True).strip()
 print(ast.literal_eval(answer.decode(UTF_)))
</code></pre>

Works for me

blocks|key|294375|text|你可以这样解决它：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|294376|s+=+"{'username':'dfdsfdsf'}"
j+=+eval(s)|code-block|syntax|javascript|294377|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

You can fix it that way:

<pre><code>s = "{'username':'dfdsfdsf'}"
j = eval(s)
</code></pre>

blocks|key|3225799|text|它确实解决了我使用eval函数的问题。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3225800|single_quoted_dict_in_string+=+"{'key':'value',+'key2':+'value2'}"
desired_double_quoted_dict+=+eval(single_quoted_dict_in_string)
#+Go+ahead,+now+you+can+convert+it+into+json+easily
print(desired_double_quoted_dict)|code-block|syntax|javascript|3225801|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

It truly solved my problem using eval function.

<pre><code>single_quoted_dict_in_string = "{'key':'value', 'key2': 'value2'}"
desired_double_quoted_dict = eval(single_quoted_dict_in_string)
# Go ahead, now you can convert it into json easily
print(desired_double_quoted_dict)
</code></pre>

blocks|key|3011805|text|到目前为止，给出了两个问题的答案，例如，如果一个流这样的非标准JSON。因为这样可能需要解释传入的字符串(而不是python字典)。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3011806|问题1-+demjson：使用Python+3.7.%2B和conda，我无法安装demjson，因为很明显，它目前不支持Python3.5。因此，我需要一个具有更简单方法的解决方案，例如ast和/或json.dumps。|offset|length|style|CODE|3011807|问题2-+ast+&+json.dumps：如果一个JSON既是单引号的，又包含至少一个值中的字符串，而该字符串又包含单引号，那么我找到的唯一简单而实用的解决方案是同时应用这两种方法：|3011808|在下面的示例中，我们假设line是传入的JSON字符串对象：|3011809|>>>+line+=+str({'abc':'008565','name':'xyz','description':'can+control+TV\'s+and+more'})|code-block|syntax|javascript|3011810|步骤1:使用ast.literal_eval()将传入的字符串转换为字典|3011811|步骤2:对其应用json.dumps以实现键和值的可靠转换，使用，但不接触值的内容|BOLD|3011812|>>>+import+ast
>>>+import+json
>>>+print(json.dumps(ast.literal_eval(line)))
{"abc":+"008565",+"name":+"xyz",+"description":+"can+control+TV's+and+more"}|3011813|单靠json.dumps是做不到这项工作的，因为它不会解释JSON，而只能看到字符串。与ast.literal_eval()类似:尽管它正确地解释了JSON+(字典)，但它不会转换我们需要的东西。|3011814|entityMap^0|0|5|7|2K|3|2Q|A|0|5|3|B|A|0|C|4|0|0|6|I|0|8|A|W|6|0|0|2|A|18|I|0^^$0|@$1|2|3|4|5|6|7|11|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|12|8|@$D|13|E|14|F|G]|$D|15|E|16|F|G]|$D|17|E|18|F|G]]|9|@]|A|$]]|$1|H|3|I|5|6|7|19|8|@$D|1A|E|1B|F|G]|$D|1C|E|1D|F|G]]|9|@]|A|$]]|$1|J|3|K|5|6|7|1E|8|@$D|1F|E|1G|F|G]]|9|@]|A|$]]|$1|L|3|M|5|N|7|1H|8|@]|9|@]|A|$O|P]]|$1|Q|3|R|5|6|7|1I|8|@$D|1J|E|1K|F|G]]|9|@]|A|$]]|$1|S|3|T|5|6|7|1L|8|@$D|1M|E|1N|F|G]|$D|1O|E|1P|F|U]]|9|@]|A|$]]|$1|V|3|W|5|N|7|1Q|8|@]|9|@]|A|$O|P]]|$1|X|3|Y|5|6|7|1R|8|@$D|1S|E|1T|F|G]|$D|1U|E|1V|F|G]]|9|@]|A|$]]|$1|Z|3|-4|5|6|7|1W|8|@]|9|@]|A|$]]]|10|$]]

Two issues with answers given so far, if , for instance, one streams such non-standard JSON. Because then one might have to interpret an incoming string (not a python dictionary). 

Issue 1 - <code>demjson</code>:
With Python 3.7.+ and using conda I wasn't able to install demjson since obviosly it does not support Python >3.5 currently. So I need a solution with simpler means, for instance <code>ast</code>and/or <code>json.dumps</code>.

Issue 2 - <code>ast</code> &amp; <code>json.dumps</code>:
If a JSON is both single quoted and contains a string in at least one value, which in turn contains single quotes, the only simple yet practical solution I have found is applying both:

In the following example we assume <code>line</code> is the incoming JSON string object :

<pre><code>&gt;&gt;&gt; line = str({'abc':'008565','name':'xyz','description':'can control TV\'s and more'})
</code></pre>

Step 1: convert the incoming string into a dictionary using <code>ast.literal_eval()</code> 
Step 2: apply <code>json.dumps</code> to it for the reliable conversion of keys and values, but without touching the contents of values:

<pre><code>&gt;&gt;&gt; import ast
&gt;&gt;&gt; import json
&gt;&gt;&gt; print(json.dumps(ast.literal_eval(line)))
{"abc": "008565", "name": "xyz", "description": "can control TV's and more"}
</code></pre>

<code>json.dumps</code> alone would not do the job because it does not interpret the JSON, but only see the string. Similar for <code>ast.literal_eval()</code>: although it interprets correctly the JSON (dictionary), it does not convert what we need.

blocks|key|289477|text|您可以使用|type|unstyled|depth|inlineStyleRanges|entityRanges|data|289478|json.dumps(your_json,+separators=(",",+":"))|code-block|syntax|javascript|289479|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

You can use
<pre><code>json.dumps(your_json, separators=(&quot;,&quot;, &quot;:&quot;))
</code></pre>

My code:

<pre><code>import simplejson as json

s = "{'username':'dfdsfdsf'}" #1
#s = '{"username":"dfdsfdsf"}' #2
j = json.loads(s)
</code></pre>

<code>#1</code> definition is wrong

<code>#2</code> definition is right

I heard that in Python that single and double quote can be interchangable. Can anyone explain this to me?

Single vs double quotes in JSON

Python

JSON

我的代码：import simplejson as jsons = "{'username':'dfdsfdsf'}" #1#s = '{"username":"dfdsfdsf"}' #2j = json.loads(s)#1定义错误#2定义是正确的我听说在Python语言中，单和双引用可以互换。有人能给我解释一下吗...

问JSON中的单引号与双引号
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