<int> = <list>.count(<el>) # Returns number of occurrences. Also works on strings.

<list>.clear() # Removes all items. Also works on dictionary and set.

<list> = <str>.split() # Splits on one or more whitespace characters.

<list> = <str>.split(sep=None, maxsplit=-1) # Splits on 'sep' str at most 'maxsplit' times.

<list> = <str>.splitlines(keepends=False) # Splits on \n,\r,\r\n. Keeps them if 'keepends'.

<bool> = <sub_str> in <str> # Checks if string contains a substring.

<bool> = <str>.startswith(<sub_str>) # Pass tuple of strings for multiple options.

<bool> = <str>.endswith(<sub_str>) # Pass tuple of strings for multiple options.

<int> = <str>.index(<sub_str>) # Same but raises ValueError if missing.

from random import random, randint, choice, shuffle, gauss, seed

<float> = random()

<int> = randint(from_inclusive, to_inclusive)

<el> = choice(<list>)

while ch != ascii.ESC:

height, _ = screen.getmaxyx()

screen.clear()

ch = screen.getch()

selected += (ch == KEY_DOWN) - (ch == KEY_UP)

selected = max(0, min(len(paths)-1, selected))

import requests, bs4, sys

try:

with open('test.png', 'wb') as file:

except requests.exceptions.ConnectionError:

print("You've got problems with connection.", file=sys.stderr)

* **Shape is a tuple of dimension sizes.**

<li><strong>Module <a href="#operator">operator</a> provides functions itemgetter() and mul() that offer the same functionality as <a href="#lambda">lambda</a> expressions above.</strong></li>

<pre><code class="python language-python hljs">&lt;int&gt; = &lt;list&gt;.count(&lt;el&gt;) <span class="hljs-comment"># Returns number of occurrences. Also works on strings.</span>

&lt;list&gt;.clear() <span class="hljs-comment"># Removes all items. Also works on dictionary and set.</span>

<div><h2 id="dictionary"><a href="#dictionary" name="dictionary">#</a>Dictionary</h2><pre><code class="python language-python hljs">&lt;view&gt; = &lt;dict&gt;.keys() <span class="hljs-comment"># Coll. of keys that reflects changes.</span>

<pre><code class="python language-python hljs">&lt;list&gt; = &lt;str&gt;.split() <span class="hljs-comment"># Splits on one or more whitespace characters.</span>

&lt;list&gt; = &lt;str&gt;.split(sep=<span class="hljs-keyword">None</span>, maxsplit=<span class="hljs-number">-1</span>) <span class="hljs-comment"># Splits on 'sep' str at most 'maxsplit' times.</span>

&lt;list&gt; = &lt;str&gt;.splitlines(keepends=<span class="hljs-keyword">False</span>) <span class="hljs-comment"># Splits on \n,\r,\r\n. Keeps them if 'keepends'.</span>

<pre><code class="python language-python hljs">&lt;bool&gt; = &lt;sub_str&gt; <span class="hljs-keyword">in</span> &lt;str&gt; <span class="hljs-comment"># Checks if string contains a substring.</span>

&lt;bool&gt; = &lt;str&gt;.startswith(&lt;sub_str&gt;) <span class="hljs-comment"># Pass tuple of strings for multiple options.</span>

&lt;bool&gt; = &lt;str&gt;.endswith(&lt;sub_str&gt;) <span class="hljs-comment"># Pass tuple of strings for multiple options.</span>

&lt;int&gt; = &lt;str&gt;.index(&lt;sub_str&gt;) <span class="hljs-comment"># Same but raises ValueError if missing.</span>

<pre><code class="python language-python hljs">&lt;str&gt; = &lt;str&gt;.replace(old, new [, count]) <span class="hljs-comment"># Replaces 'old' with 'new' at most 'count' times.</span>

<div><h3 id="random">Random</h3><pre><code class="python language-python hljs"><span class="hljs-keyword">from</span> random <span class="hljs-keyword">import</span> random, randint, choice, shuffle, gauss, seed

&lt;float&gt; = random()

&lt;int&gt; = randint(from_inclusive, to_inclusive)

&lt;el&gt; = choice(&lt;list&gt;)

<div><h3 id="binhex">Bin, Hex</h3><pre><code class="python language-python hljs">&lt;int&gt; = ±<span class="hljs-number">0</span>b&lt;bin&gt; <span class="hljs-comment"># Or: ±0x&lt;hex&gt;</span>

<span class="hljs-keyword">while</span> ch != ascii.ESC:

height, _ = screen.getmaxyx()

screen.clear()

ch = screen.getch()

selected += (ch == KEY_DOWN) - (ch == KEY_UP)

selected = max(<span class="hljs-number">0</span>, min(len(paths)<span class="hljs-number">-1</span>, selected))

<div><h2 id="scraping"><a href="#scraping" name="scraping">#</a>Scraping</h2><div><h4 id="scrapespythonsurlversionnumberandlogofromitswikipediapage">Scrapes Python's URL, version number and logo from its Wikipedia page:</h4><pre><code class="python language-python hljs"><span class="hljs-comment"># $ pip3 install requests beautifulsoup4</span>

<span class="hljs-keyword">import</span> requests, bs4, sys

<span class="hljs-keyword">try</span>:

<span class="hljs-keyword">with</span> open(<span class="hljs-string">'test.png'</span>, <span class="hljs-string">'wb'</span>) <span class="hljs-keyword">as</span> file:

<span class="hljs-keyword">except</span> requests.exceptions.ConnectionError:

print(<span class="hljs-string">"You've got problems with connection."</span>, file=sys.stderr)

<li><strong>Shape is a tuple of dimension sizes.</strong></li>

<div><h3 id="indexing">Indexing</h3><pre><code class="python language-python hljs">&lt;el&gt; = &lt;2d_array&gt;[<span class="hljs-number">0</span>, <span class="hljs-number">0</span>] <span class="hljs-comment"># First element.</span>

&lt;1d_view&gt; = &lt;2d_array&gt;[<span class="hljs-number">0</span>] <span class="hljs-comment"># First row.</span>