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Python | Test for False list
• Last Updated : 04 Jan, 2019

Sometimes, we need to check if a list is completely True of False, these occurrences come more often in testing purposes after the development phase. Hence, having a knowledge of all this is necessary and useful. Lets discuss certain ways in which this can be performed.

Method #1 : Naive Method
In the naive method, we just run a loop from beg to end of list and check manually for each value. This is the most basic way to perform this particular task.

 `# Python3 code to demonstrate  ` `# to check for False list  ` `# using naive method ` ` `  `# initializing list   ` `test_list ``=` `[``False``, ``False``, ``False``, ``False``] ` ` `  `# printing original list ` `print` `(``"The original list is : "` `+` `str``(test_list)) ` ` `  `flag ``=` `0` ` `  `# using naive method  ` `# to check for False list  ` `for` `i ``in` `test_list : ` `    ``if` `i ``=``=` `True` `: ` `        ``flag ``=` `1` `        ``break` ` `  `# printing result ` `print` `(``"Is List completely false ? : "` `+`  `str``(``bool``(``not` `flag))) `

Output:

```The original list is : [False, False, False, False]
Is List completely false ? : True
```

Method #2 : Using `all()`
This function tests each value to be False and if yes, returns boolean True, else returns false. The list iteration is done using list comprehension.

 `# Python3 code to demonstrate  ` `# to check for False list  ` `# using all() ` ` `  `# initializing list   ` `test_list ``=` `[``False``, ``False``, ``False``, ``False``] ` ` `  `# printing original list ` `print` `(``"The original list is : "` `+` `str``(test_list)) ` ` `  `flag ``=` `0` ` `  `# using all() ` `# to check for False list  ` `res ``=` `all``(``not` `i ``for` `i ``in` `test_list) ` ` `  `# printing result ` `print` `(``"Is List completely false ? : "` `+`  `str``(res)) `

Output:

```The original list is : [False, False, False, False]
Is List completely false ? : True
```

Method #3 : Using `any()`
This function tests for any one of the True value, if found returns True, else returns False value. Negation of this function is used as the result.

 `# Python3 code to demonstrate  ` `# to check for False list  ` `# using any() ` ` `  `# initializing list   ` `test_list ``=` `[``False``, ``False``, ``False``, ``False``] ` ` `  `# printing original list ` `print` `(``"The original list is : "` `+` `str``(test_list)) ` ` `  `# using any() ` `# to check for False list  ` `res ``=` `not` `any``(test_list) ` ` `  `# printing result ` `print` `(``"Is List completely false ? : "` `+`  `str``(res)) `

Output:

```The original list is : [False, False, False, False]
Is List completely false ? : True
```

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