/// tip

For this to work, you need to `pip install python-dotenv`.

///

### The `.env` file { #the-env-file }

You could have a `.env` file with:

```bash
ADMIN_EMAIL="******@****.***"
APP_NAME="ChimichangApp"
```

			log.Printf("failed to ping sqlDB, got error %v", err)
			os.Exit(1)
		}

		RunMigrations()
	}
}

func OpenTestConnection(cfg *gorm.Config) (db *gorm.DB, err error) {
	dbDSN := os.Getenv("GORM_DSN")
	switch os.Getenv("GORM_DIALECT") {
	case "mysql":
		log.Println("testing mysql...")
		if dbDSN == "" {
			dbDSN = mysqlDSN
		}
		db, err = gorm.Open(mysql.Open(dbDSN), cfg)
	case "postgres":

     *
     * @param key the environment variable key
     * @return the environment variable value, or null if not found
     */
    public static String getEnv(String key) {
        return System.getenv(key);
    }

    /**
     * Returns the system environment variable value for the specified key, or the default value if not found.
     *
     * @param key the environment variable key

مثلاً می‌تونی یه فایل `main.py` داشته باشی با:

```Python hl_lines="3"
import os

name = os.getenv("MY_NAME", "World")
print(f"Hello {name} from Python")
```

/// tip

آرگومان دوم <a href="https://docs.python.org/3.8/library/os.html#os.getenv" class="external-link" target="_blank">`os.getenv()`</a> مقدار پیش‌فرضیه که برمی‌گردونه.

For example you could have a file `main.py` with:

```Python hl_lines="3"
import os

name = os.getenv("MY_NAME", "World")
print(f"Hello {name} from Python")
```

/// tip

The second argument to <a href="https://docs.python.org/3.8/library/os.html#os.getenv" class="external-link" target="_blank">`os.getenv()`</a> is the default value to return.

        }
        if (generatorList != null && !generatorList.isEmpty()) {
            String path = System.getenv("PATH");
            if (path == null) {
                path = System.getenv("Path");
            }
            if (path == null) {
                path = System.getenv("path");
            }
            final List<String> pathList = new ArrayList<>();
            pathList.add("/usr/share/fess/bin");

include(":samples:static-server")
include(":samples:tlssurvey")
include(":samples:unixdomainsockets")
include(":container-tests")

project(":okhttp-logging-interceptor").name = "logging-interceptor"

val androidHome = System.getenv("ANDROID_HOME")
val localProperties = Properties().apply {
  val file = File("local.properties")
  if (file.exists()) {
    load(file.inputStream())
  }
}
val sdkDir = localProperties.getProperty("sdk.dir")

	public class Downloader extends java.net.Authenticator
	{
	  protected java.net.PasswordAuthentication getPasswordAuthentication()
	  {
	    return new java.net.PasswordAuthentication( System.getenv( "MVNW_USERNAME" ), System.getenv( "MVNW_PASSWORD" ).toCharArray() );
	  }
	  public static void main( String[] args ) throws Exception
	  {
	    setDefault( new Downloader() );

     *
     * @return the application type string, or empty string if not set
     */
    public static String getAppType() {
        final String appType = System.getenv(FESS_APP_TYPE);
        if (StringUtil.isNotBlank(appType)) {
            return appType;
        }
        return StringUtil.EMPTY;
    }

    /**

        final Hashtable<String, String> env = new Hashtable<>();
        putEnv(env, Context.INITIAL_CONTEXT_FACTORY, initialContextFactory);
        putEnv(env, Context.SECURITY_AUTHENTICATION, securityAuthentication);
        putEnv(env, Context.PROVIDER_URL, providerUrl);
        putEnv(env, Context.SECURITY_PRINCIPAL, principal);
        putEnv(env, Context.SECURITY_CREDENTIALS, credntials);