blocks|key|2491616|text|正如所描述的注释，它只是引用计算为True或False的值。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2491617|例如，要查看列表是否不为空，而不是像这样检查：|2491618|if+len(my_list)+!=+0:
+++print("Not+empty!")|code-block|syntax|javascript|2491619|您可以简单地执行以下操作：|2491620|if+my_list:
+++print("Not+empty!")|2491621|这是因为一些值，例如空列表，在计算布尔值时被认为是假的。非空列表为True。|2491622|同样，对于整数0、空字符串"“等等，对于False，对于True，对于非零整数、非空字符串等等。|2491623|像“真”和“假”这样的术语只是指那些在上述情况下被认为是真的值，以及那些被认为是假的值。|2491624|例如，一个空的列表([])被认为是“假的”，一个非空的列表(例如，[1])被认为是“真的”。|offset|length|style|CODE|2491625|另请参见this+section+of+the+documentation。|2491626|entityMap|0|LINK|mutability|MUTABLE|url|https://docs.python.org/3/library/stdtypes.html#truth-value-testing^0|0|0|0|0|0|0|0|0|A|2|X|3|0|4|X|0|0^^$0|@$1|2|3|4|5|6|7|18|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|19|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|1A|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|1B|8|@]|9|@]|A|$]]|$1|K|3|L|5|F|7|1C|8|@]|9|@]|A|$G|H]]|$1|M|3|N|5|6|7|1D|8|@]|9|@]|A|$]]|$1|O|3|P|5|6|7|1E|8|@]|9|@]|A|$]]|$1|Q|3|R|5|6|7|1F|8|@]|9|@]|A|$]]|$1|S|3|T|5|6|7|1G|8|@$U|1H|V|1I|W|X]|$U|1J|V|1K|W|X]]|9|@]|A|$]]|$1|Y|3|Z|5|6|7|1L|8|@]|9|@$U|1M|V|1N|1|1O]]|A|$]]|$1|10|3|-4|5|6|7|1P|8|@]|9|@]|A|$]]]|11|$12|$5|13|14|15|A|$16|17]]]]

As the comments described, it just refers to values which are evaluated to True or False.

For instance, to see if a list is not empty, instead of checking like this:

<pre><code>if len(my_list) != 0:
 print("Not empty!")
</code></pre>

You can simply do this:

<pre><code>if my_list:
 print("Not empty!")
</code></pre>

This is because some values, such as empty lists, are considered False when evaluated for a boolean value. Non-empty lists are True.

Similarly for the integer 0, the empty string "", and so on, for False, and non-zero integers, non-empty strings, and so on, for True.

The idea of terms like "truthy" and "falsy" simply refer to those values which are considered True in cases like those described above, and those which are considered False.

For example, an empty list (<code>[]</code>) is considered "falsy", and a non-empty list (for example, <code>[1]</code>) is considered "truthy".

See also <a href="https://docs.python.org/3/library/stdtypes.html#truth-value-testing" rel="noreferrer">this section of the documentation</a>.

blocks|key|30140|text|所有的值都被认为是“真的”，除了下面这些值是“假的”：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|30141|30142|None|unordered-list-item|offset|length|style|CODE|30143|False|30144|0|30145|0.0|30146|0j|30147|decimal.Decimal(0)|30148|fraction.Fraction(0,+1)|30149|[]+-一个空list|30150|{}+-一个空dict|30151|()+-一个空tuple|30152|''+-一个空str|30153|b''+-一个空bytes|30154|set()+-一个空set|30155|an空range，像range(0)|30156|objects一样，|30157|obj.__bool__()返回False|30158|obj.__len__()，返回0|30159|30160|30161|"truthy“值将满足if或while语句执行的检查。我们使用"truthy“和"falsy”来区别于bool值True和False。|30162|30163|entityMap|LINK|mutability|MUTABLE|url|https://docs.python.org/3/library/decimal.html#decimal.Decimal|1|https://docs.python.org/3/library/fractions.html#fractions.Fraction^0|0|0|0|4|0|0|5|0|0|1|0|0|3|0|0|2|0|0|I|0|I|0|0|0|N|0|N|1|0|0|2|7|4|0|0|2|7|4|0|0|2|7|5|0|0|2|7|3|0|0|3|8|5|0|0|5|A|3|0|3|5|A|8|0|1|0|E|G|5|1|0|D|G|1|1|0|0|C|2|F|5|1G|4|1L|4|1Q|5|0|0^^$0|@$1|2|3|4|5|6|7|1T|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|1U|8|@]|9|@]|A|$]]|$1|C|3|D|5|E|7|1V|8|@$F|1W|G|1X|H|I]]|9|@]|A|$]]|$1|J|3|K|5|E|7|1Y|8|@$F|1Z|G|20|H|I]]|9|@]|A|$]]|$1|L|3|M|5|E|7|21|8|@$F|22|G|23|H|I]]|9|@]|A|$]]|$1|N|3|O|5|E|7|24|8|@$F|25|G|26|H|I]]|9|@]|A|$]]|$1|P|3|Q|5|E|7|27|8|@$F|28|G|29|H|I]]|9|@]|A|$]]|$1|R|3|S|5|E|7|2A|8|@$F|2B|G|2C|H|I]]|9|@$F|2D|G|2E|1|2F]]|A|$]]|$1|T|3|U|5|E|7|2G|8|@$F|2H|G|2I|H|I]]|9|@$F|2J|G|2K|1|2L]]|A|$]]|$1|V|3|W|5|E|7|2M|8|@$F|2N|G|2O|H|I]|$F|2P|G|2Q|H|I]]|9|@]|A|$]]|$1|X|3|Y|5|E|7|2R|8|@$F|2S|G|2T|H|I]|$F|2U|G|2V|H|I]]|9|@]|A|$]]|$1|Z|3|10|5|E|7|2W|8|@$F|2X|G|2Y|H|I]|$F|2Z|G|30|H|I]]|9|@]|A|$]]|$1|11|3|12|5|E|7|31|8|@$F|32|G|33|H|I]|$F|34|G|35|H|I]]|9|@]|A|$]]|$1|13|3|14|5|E|7|36|8|@$F|37|G|38|H|I]|$F|39|G|3A|H|I]]|9|@]|A|$]]|$1|15|3|16|5|E|7|3B|8|@$F|3C|G|3D|H|I]|$F|3E|G|3F|H|I]]|9|@]|A|$]]|$1|17|3|18|5|E|7|3G|8|@$F|3H|G|3I|H|I]|$F|3J|G|3K|H|I]]|9|@]|A|$]]|$1|19|3|1A|5|E|7|3L|8|@]|9|@]|A|$]]|$1|1B|3|1C|5|E|7|3M|8|@$F|3N|G|3O|H|I]|$F|3P|G|3Q|H|I]]|9|@]|A|$]]|$1|1D|3|1E|5|E|7|3R|8|@$F|3S|G|3T|H|I]|$F|3U|G|3V|H|I]]|9|@]|A|$]]|$1|1F|3|-4|5|6|7|3W|8|@]|9|@]|A|$]]|$1|1G|3|-4|5|6|7|3X|8|@]|9|@]|A|$]]|$1|1H|3|1I|5|6|7|3Y|8|@$F|3Z|G|40|H|I]|$F|41|G|42|H|I]|$F|43|G|44|H|I]|$F|45|G|46|H|I]|$F|47|G|48|H|I]]|9|@]|A|$]]|$1|1J|3|-4|5|6|7|49|8|@]|9|@]|A|$]]|$1|1K|3|-4|5|6|7|4A|8|@]|9|@]|A|$]]]|1L|$M|$5|1M|1N|1O|A|$1P|1Q]]|1R|$5|1M|1N|1O|A|$1P|1S]]]]

All values are considered &quot;truthy&quot; except for the following, which are &quot;falsy&quot;:
<ul>
<li><code>None</code></li>
<li><code>False</code></li>
<li><code>0</code></li>
<li><code>0.0</code></li>
<li><code>0j</code></li>
<li><a href="https://docs.python.org/3/library/decimal.html#decimal.Decimal" rel="noreferrer"><code>decimal.Decimal(0)</code></a></li>
<li><a href="https://docs.python.org/3/library/fractions.html#fractions.Fraction" rel="noreferrer"><code>fraction.Fraction(0, 1)</code></a></li>
<li><code>[]</code> - an empty <code>list</code></li>
<li><code>{}</code> - an empty <code>dict</code></li>
<li><code>()</code> - an empty <code>tuple</code></li>
<li><code>''</code> - an empty <code>str</code></li>
<li><code>b''</code> - an empty <code>bytes</code></li>
<li><code>set()</code> - an empty <code>set</code></li>
<li>an empty <code>range</code>, like <code>range(0)</code></li>
<li>objects for which
<ul>
<li><code>obj.__bool__()</code> returns <code>False</code></li>
<li><code>obj.__len__()</code> returns <code>0</code></li>
</ul>
</li>
</ul>
A &quot;truthy&quot; value will satisfy the check performed by <code>if</code> or <code>while</code> statements. We use &quot;truthy&quot; and &quot;falsy&quot; to differentiate from the <code>bool</code> values <code>True</code> and <code>False</code>.
<a href="https://docs.python.org/3/library/stdtypes.html#truth-value-testing" rel="noreferrer">Truth Value Testing</a>

blocks|key|29882|text|Python通过将bool()应用于类型来确定真实性，这将返回True或False，这是在if或while等表达式中使用的。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|29883|下面是一个自定义类Vector2d的示例，当模(向量的长度)为0时，它的实例返回False，否则返回True。|29884|import+math
class+Vector2d(object):
++++def+__init__(self,+x,+y):
++++++++self.x+=+float(x)
++++++++self.y+=+float(y)

++++def+__abs__(self):
++++++++return+math.hypot(self.x,+self.y)

++++def+__bool__(self):
++++++++return+bool(abs(self))

a+=+Vector2d(0,0)
print(bool(a))++++++++#False
b+=+Vector2d(10,0)++++
print(bool(b))++++++++#True|code-block|syntax|javascript|29885|注意：如果我们没有定义__bool__，它将总是返回True，因为用户定义的类的实例在默认情况下被认为是True。|BOLD|29886|书中的示例：“流利的Python，清晰、简洁和有效的编程”|29887|entityMap^0|9|6|V|4|10|5|19|2|1C|5|0|9|8|14|5|1E|4|0|0|0|3|B|8|0|0^^$0|@$1|2|3|4|5|6|7|T|8|@$9|U|A|V|B|C]|$9|W|A|X|B|C]|$9|Y|A|Z|B|C]|$9|10|A|11|B|C]|$9|12|A|13|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|14|8|@$9|15|A|16|B|C]|$9|17|A|18|B|C]|$9|19|A|1A|B|C]]|D|@]|E|$]]|$1|H|3|I|5|J|7|1B|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|6|7|1C|8|@$9|1D|A|1E|B|O]|$9|1F|A|1G|B|C]]|D|@]|E|$]]|$1|P|3|Q|5|6|7|1H|8|@]|D|@]|E|$]]|$1|R|3|-4|5|6|7|1I|8|@]|D|@]|E|$]]]|S|$]]

Python determines the truthiness by applying <code>bool()</code> to the type, which returns <code>True</code> or <code>False</code> which is used in an expression like <code>if</code> or <code>while</code>. 

Here is an example for a custom class <code>Vector2d</code>and it's instance returning <code>False</code> when the magnitude (lenght of a vector) is 0, otherwise <code>True</code>.

<pre><code>import math
class Vector2d(object):
 def __init__(self, x, y):
 self.x = float(x)
 self.y = float(y)

 def __abs__(self):
 return math.hypot(self.x, self.y)

 def __bool__(self):
 return bool(abs(self))

a = Vector2d(0,0)
print(bool(a)) #False
b = Vector2d(10,0) 
print(bool(b)) #True
</code></pre>

Note: If we wouldn't have defined <code>__bool__</code> it would always return True, as instances of a user-defined class are considered truthy by default.

Example from the book: "Fluent in Python, clear, concise and effective programming"

blocks|key|31477|text|TRUTH值指的是布尔上下文中使用的对象，而不是返回true或false.Take的布尔值，例如：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|31478|>>>+bool([])
False
>>>+bool([1])
True
>>>+bool('')
False
>>>+bool('hello')
True|code-block|syntax|javascript|31479|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|$]]

Truthy values refer to the objects used in a boolean context and not so much the boolean value that returns true or false.Take these as an example:

<pre><code>&gt;&gt;&gt; bool([])
False
&gt;&gt;&gt; bool([1])
True
&gt;&gt;&gt; bool('')
False
&gt;&gt;&gt; bool('hello')
True
</code></pre>

blocks|key|29912|text|您应该在哪里使用Truthy或Falsy值？这些都是语法糖，所以您总是可以避免使用它们，但是使用它们可以使您的代码更具可读性，并使您更有效率。此外，您将在许多代码示例中找到它们，无论是否使用python，因为它被认为是很好的实践。|type|unstyled|depth|inlineStyleRanges|offset|length|style|BOLD|entityRanges|data|29913|正如在其他答案中提到的，您可以在if测试和while循环中使用它们。下面是Python3中的另外两个示例，默认值与or组合在一起，s是一个字符串变量。您也将扩展到类似的情况。|CODE|29914|没有真实性|29915|if+len(s)+>+0:
++++print(s)
else:
++++print('Default+value')|code-block|syntax|javascript|29916|与truthy一起使用时，它更简洁：|29917|print(s+or+'Default+value')|29918|在Python3.8中，我们可以利用赋值表达式:=|29919|29920|if+len(s)+==+0:
++++s+=+'Default+value'
do_something(s)|29921|对于too，它也更短。|29922|s+or+(s+:=+'Default+value')
do_something(s)|29923|或者更短，|29924|do_something(s+or+(s+:=+'Default+value'))|29925|在没有赋值表达式的情况下，可以|29926|s+=+s+or+'Default+value'
do_something(s)|29927|但不是更短。有些人觉得s+=...行不能令人满意，因为它对应于|29928|if+len(s)>0:
++++s+=+s+#+HERE+is+an+extra+useless+assignment
else:
++++s+=+"Default+value"|29929|但是，如果您对此编码风格感到满意，则可以坚持使用它。|29930|entityMap^0|Q|3|0|1L|2|1T|1|0|0|0|0|0|N|2|0|0|0|0|0|0|0|0|0|B|6|0|0|0^^$0|@$1|2|3|4|5|6|7|1I|8|@$9|1J|A|1K|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|1L|8|@$9|1M|A|1N|B|H]|$9|1O|A|1P|B|H]]|D|@]|E|$]]|$1|I|3|J|5|6|7|1Q|8|@]|D|@]|E|$]]|$1|K|3|L|5|M|7|1R|8|@]|D|@]|E|$N|O]]|$1|P|3|Q|5|6|7|1S|8|@]|D|@]|E|$]]|$1|R|3|S|5|M|7|1T|8|@]|D|@]|E|$N|O]]|$1|T|3|U|5|6|7|1U|8|@$9|1V|A|1W|B|H]]|D|@]|E|$]]|$1|V|3|J|5|6|7|1X|8|@]|D|@]|E|$]]|$1|W|3|X|5|M|7|1Y|8|@]|D|@]|E|$N|O]]|$1|Y|3|Z|5|6|7|1Z|8|@]|D|@]|E|$]]|$1|10|3|11|5|M|7|20|8|@]|D|@]|E|$N|O]]|$1|12|3|13|5|6|7|21|8|@]|D|@]|E|$]]|$1|14|3|15|5|M|7|22|8|@]|D|@]|E|$N|O]]|$1|16|3|17|5|6|7|23|8|@]|D|@]|E|$]]|$1|18|3|19|5|M|7|24|8|@]|D|@]|E|$N|O]]|$1|1A|3|1B|5|6|7|25|8|@$9|26|A|27|B|H]]|D|@]|E|$]]|$1|1C|3|1D|5|M|7|28|8|@]|D|@]|E|$N|O]]|$1|1E|3|1F|5|6|7|29|8|@]|D|@]|E|$]]|$1|1G|3|-4|5|6|7|2A|8|@]|D|@]|E|$]]]|1H|$]]

Where should you use Truthy or Falsy values ?
These are syntactic sugar, so you can always avoid them, but using them can make your code more readable and make you more efficient.
Moreover, you will find them in many code examples, whether in python or not, because it is considered good practice.

As mentioned in the other answers, you can use them in if tests and while loops. Here are two other examples in python 3 with default values combined with <code>or</code>, <code>s</code> being a string variable. You will extend to similar situations as well.

Without truthy

<pre><code>if len(s) &gt; 0:
 print(s)
else:
 print('Default value')
</code></pre>

with truthy it is more concise:

<pre><code>print(s or 'Default value')
</code></pre>

In python 3.8, we can take advantage of the assignment expression <code>:=</code>

without truthy

<pre><code>if len(s) == 0:
 s = 'Default value'
do_something(s)
</code></pre>

with truthy it is shorter too

<pre><code>s or (s := 'Default value')
do_something(s)
</code></pre>

or even shorter,

<pre><code>do_something(s or (s := 'Default value'))
</code></pre>

Without the assignment expression, one can do

<pre><code>s = s or 'Default value'
do_something(s)
</code></pre>

but not shorter. Some people find the <code>s =...</code> line unsatisfactory because it corresponds to

<pre><code>if len(s)&gt;0:
 s = s # HERE is an extra useless assignment
else:
 s = "Default value"
</code></pre>

nevertheless you can adhere to this coding style if you feel comfortable with it.

blocks|key|2702304|text|Falsy表示空的东西，例如空列表、元组，以及任何具有空值或没有值的数据类型。真理的意思是:除了真理之外|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2702305|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

Falsy means something empty like empty list,tuple, as any datatype having empty values or None.
Truthy means : 
Except are Truthy

blocks|key|2491944|text|如果是if+(!id)+{}|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|2491945|!expr如果其单个操作数可以转换为true，则返回false；否则返回true。|2491946|如果一个值可以转换为true，那么这个值就是所谓的true。如果一个值可以转换为false，那么这个值就是所谓的false。|2491947|可以转换为false的表达式示例如下：|2491948|null;

NaN;

0;

empty+string+(""+or+''+or+``);

undefined.|code-block|syntax|javascript|2491949|尽管!运算符可以与非布尔值的操作数一起使用，但它仍然可以被视为布尔运算符，因为它的返回值始终可以转换为布尔原语。要显式地将其返回值(或一般情况下的任何表达式)转换为相应的布尔值，请使用双NOT运算符或布尔构造函数。|2491950|示例：|2491951|n1+=+!null+++++++++++++++//+!t+returns+true
n2+=+!NaN++++++++++++++//+!f+returns+true
n3+=+!''+++++++++++++++++//+!f+returns+true
n4+=+!'Cat'++++++++++++++//+!t+returns+false|2491952|而对于if+(id+!=+null)+{}，它将只检查id中的值是否不等于null|2491953|参考https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Logical_NOT|2491954|entityMap|0|LINK|mutability|MUTABLE|url|https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Logical_NOT^0|3|B|0|I|4|Q|5|10|4|0|0|0|0|2|1|0|0|0|3|I|0|2|2F|0|0^^$0|@$1|2|3|4|5|6|7|18|8|@$9|19|A|1A|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|1B|8|@$9|1C|A|1D|B|C]|$9|1E|A|1F|B|C]|$9|1G|A|1H|B|C]]|D|@]|E|$]]|$1|H|3|I|5|6|7|1I|8|@]|D|@]|E|$]]|$1|J|3|K|5|6|7|1J|8|@]|D|@]|E|$]]|$1|L|3|M|5|N|7|1K|8|@]|D|@]|E|$O|P]]|$1|Q|3|R|5|6|7|1L|8|@$9|1M|A|1N|B|C]]|D|@]|E|$]]|$1|S|3|T|5|6|7|1O|8|@]|D|@]|E|$]]|$1|U|3|V|5|N|7|1P|8|@]|D|@]|E|$O|P]]|$1|W|3|X|5|6|7|1Q|8|@$9|1R|A|1S|B|C]]|D|@]|E|$]]|$1|Y|3|Z|5|6|7|1T|8|@]|D|@$9|1U|A|1V|1|1W]]|E|$]]|$1|10|3|-4|5|6|7|1X|8|@]|D|@]|E|$]]]|11|$12|$5|13|14|15|E|$16|17]]]]

In case of <code>if (!id) {}</code>
!expr returns <code>false</code> if its single operand can be converted to <code>true</code>; otherwise, returns <code>true</code>.
If a value can be converted to true, the value is so-called truthy. If a value can be converted to false, the value is so-called falsy.
Examples of expressions that can be converted to false are:
<pre><code>null;

NaN;

0;

empty string (&quot;&quot; or '' or ``);

undefined.
</code></pre>
Even though the <code>!</code> operator can be used with operands that are not Boolean values, it can still be considered a boolean operator since its return value can always be converted to a boolean primitive. To explicitly convert its return value (or any expression in general) to the corresponding boolean value, use a double NOT operator or the Boolean constructor.
Example:
<pre><code>n1 = !null // !t returns true
n2 = !NaN // !f returns true
n3 = !'' // !f returns true
n4 = !'Cat' // !t returns false
</code></pre>
While in case of <code>if (id != null) {}</code> it will only check if the value in id is not equal to null
reference <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Logical_NOT" rel="nofollow noreferrer">https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Logical_NOT</a>

blocks|key|2492111|text|Python中的任何对象都可以测试其真值。它可以在if或while条件中使用，也可以作为布尔运算的操作数使用。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2492112|下列值被认为是False|offset|length|style|CODE|2492113|任何数值类型的|2492114|None|unordered-list-item|2492115|False|2492116|zero，例如，0，0L，0.0，0j。当该方法返回整数零或布尔值False.|2492117|时，|2492118|任何空序列，例如，''，()，[]。|2492119|
|2492120|任何空映射，例如，用户定义类的__nonzero__()或__len__()方法|2492121|2492122|所有其他值都被认为是True+--因此许多类型的对象总是真的。|2492123|除非另有说明，否则具有布尔结果的操作和内置函数总是返回0或False表示false，返回1或True表示true。|2492124|entityMap^0|0|7|5|0|0|0|4|0|0|5|0|X|5|0|0|0|0|F|D|T|9|0|0|A|4|0|T|5|1A|4|0^^$0|@$1|2|3|4|5|6|7|15|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|16|8|@$D|17|E|18|F|G]]|9|@]|A|$]]|$1|H|3|I|5|6|7|19|8|@]|9|@]|A|$]]|$1|J|3|K|5|L|7|1A|8|@$D|1B|E|1C|F|G]]|9|@]|A|$]]|$1|M|3|N|5|L|7|1D|8|@$D|1E|E|1F|F|G]]|9|@]|A|$]]|$1|O|3|P|5|L|7|1G|8|@$D|1H|E|1I|F|G]]|9|@]|A|$]]|$1|Q|3|R|5|6|7|1J|8|@]|9|@]|A|$]]|$1|S|3|T|5|L|7|1K|8|@]|9|@]|A|$]]|$1|U|3|V|5|6|7|1L|8|@]|9|@]|A|$]]|$1|W|3|X|5|L|7|1M|8|@$D|1N|E|1O|F|G]|$D|1P|E|1Q|F|G]]|9|@]|A|$]]|$1|Y|3|-4|5|6|7|1R|8|@]|9|@]|A|$]]|$1|Z|3|10|5|6|7|1S|8|@$D|1T|E|1U|F|G]]|9|@]|A|$]]|$1|11|3|12|5|6|7|1V|8|@$D|1W|E|1X|F|G]|$D|1Y|E|1Z|F|G]]|9|@]|A|$]]|$1|13|3|-4|5|6|7|20|8|@]|9|@]|A|$]]]|14|$]]

Any object in Python can be tested for its truth value. It can be used in an if or while condition or as operand of the Boolean operations.
The following values are considered <code>False</code>:
<ul>
<li><code>None</code></li>
<li><code>False</code></li>
<li>zero of any numeric type, for example, 0, 0L, 0.0, 0j.</li>
<li>any empty sequence, for example, '', (), [].</li>
<li>any empty mapping, for example, {}.</li>
<li>instances of user-defined classes, if the class defines a <code>__nonzero__()</code> or <code>__len__()</code> method, when that method returns the integer zero or bool value <code>False</code>.</li>
</ul>
All other values are considered <code>True</code> -- thus objects of many types are always true.
Operations and built-in functions that have a Boolean result always return 0 or <code>False</code> for false and 1 or <code>True</code> for true, unless otherwise stated.

I just learned there are truthy and falsy values in python which are different from the normal <code>True</code> and <code>False</code>.
Can someone please explain in depth what truthy and falsy values are? Where should I use them? What is the difference between truthy and <code>True</code> values and falsy and <code>False</code> values?

What is Truthy and Falsy? How is it different from True and False?

Python

我刚刚了解到在python中有truthy和falsy的值，这与正常的True和False不同。有没有人能深入解释一下真假价值观是什么？我应该在哪里使用它们？truthy和True值与falsy和False值之间有什么区别？

问什么是真与假？它与True和False有什么不同？
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