# Variables d'environnement { #environment-variables }

/// tip | Astuce

Si vous savez déjà ce que sont les « variables d'environnement » et comment les utiliser, vous pouvez passer cette section.

///

Une variable d'environnement (également appelée « env var ») est une variable qui vit en dehors du code Python, dans le système d'exploitation, et qui peut être lue par votre code Python (ou par d'autres programmes également).

Hello Wade Wilson from Python

// The env var no longer exists afterwards
$ python main.py

Hello World from Python
```

</div>

/// tip

You can read more about it at [The Twelve-Factor App: Config](https://12factor.net/config).

///

## Types and Validation { #types-and-validation }

  var previousMappedRanges: List<MappedRange>? = null

  for ((section, sectionMappedRanges) in sections) {
    // Skip sequential ranges when they are equal.
    if (sectionMappedRanges == previousMappedRanges) continue
    previousMappedRanges = sectionMappedRanges

    val sectionOffset = rangesBuffer.size.toInt() / 4

    // Section prefix.
    sectionIndexBuffer.writeByte(section and 0x1fc000 shr 14)

                Map.of("_default", List.of("QUERY1")), //
                Set.of("QUERY1"), //

    return files


def generate_renamed_section_items(
    items: list[Page | Section | Link], *, config: MkDocsConfig
) -> list[Page | Section | Link]:
    new_items: list[Page | Section | Link] = []
    for item in items:
        if isinstance(item, Section):
            new_title = item.title
            new_children = generate_renamed_section_items(item.children, config=config)

 * bits.
 *
 * We split each code point into a 14-bit prefix and a 7-bit suffix. All code points with the same
 * prefix are called a 'section'. There are 128 code points per section.
 *
 * Ranges Data (32,612 bytes)
 * ==========================
 *
 * Each entry is 4 bytes, and represents a _range_ of code points that all share a common 14-bit

}

#result .title {
	margin: 1.0em 0 0.5em 0;
	font-size: 120%;
	font-weight: 600;
}

section.content table {
	display: table;
	table-layout: fixed;
	width: 100%;
}

section.content table td {
	display: table-cell;
	word-wrap: break-word;
	overflow-wrap: break-word;
}

section.content table .label {
	color: #fff;
}

textarea.systemInfoData {
	height: 22em;
	line-height: 1.5em;

  /**
   * The "base64" base encoding specified by <a
   * href="http://tools.ietf.org/html/rfc4648#section-4">RFC 4648 section 4</a>, Base 64 Encoding.
   * (This is the same as the base 64 encoding from <a
   * href="http://tools.ietf.org/html/rfc3548#section-3">RFC 3548</a>.)
   *
   * <p>The character {@code '='} is used for padding, but can be {@linkplain #omitPadding()

        fw.println("# * Inside the same file: <<(#)section-name(,text)>>");
        fw.println("# * To a different file: <<other-file(.adoc)#section-name,text>> - Note that the # and section are mandatory, otherwise the link is invalid in the single page output");
        fw.println("#");
        fw.println("# The checker does not handle implicit section names, so they must be explicit and declared as: [[section-name]]");
        fw.println("#");

  /**
   * The HTTP <a href="https://wicg.github.io/ua-client-hints/#sec-ch-ua-form-factor">{@code
   * Sec-CH-UA-Form-Factor}</a> header field name.
   *
   * @deprecated Prefer {@link SEC_CH_UA_FORM_FACTORS}.
   * @since 32.0.0
   */
  @Deprecated public static final String SEC_CH_UA_FORM_FACTOR = "Sec-CH-UA-Form-Factor";

  /**