```Python hl_lines="10"
{!> ../../docs_src/path_params_numeric_validations/tutorial001.py!}
```

////

/// note

A path parameter is always required as it has to be part of the path. Even if you declared it with `None` or set a default value, it would not affect anything, it would still be always required.

///

## Order the parameters as you need

/// tip

Het tweede argument van <a href="https://docs.python.org/3.8/library/os.html#os.getenv" class="external-link" target="_blank">`os.getenv()`</a> is de standaardwaarde die wordt geretourneerd.

Als je dit niet meegeeft, is de standaardwaarde `None`. In dit geval gebruiken we standaard `"World"`.

///

Dan zou je dat Python-programma kunnen aanroepen:

//// tab | Linux, macOS, Windows Bash

<div class="termy">

```console

   * to thread contention. But overestimates and underestimates within an order of magnitude do not
   * usually have much noticeable impact. A value of one permits only one thread to modify the cache
   * at a time, but since read operations and cache loading computations can proceed concurrently,
   * this still yields higher concurrency than full synchronization.
   *

    port = serverSocket!!.localPort
    executor.execute {
      try {
        readAndWriteFrames()
      } catch (e: IOException) {
        ******@****.***uietly()
        logger.info("${this@MockHttp2Peer} done: ${e.message}")
      }
    }
  }

  private fun readAndWriteFrames() {
    check(socket == null)
    val socket = serverSocket!!.accept()!!
    this.socket = socket

      lastItem = tmp;
    }
    assertEquals((Integer) 30, lastItem);
  }

  /**
   * This tests a special case where removeAt has to trickle an element first down one level from a
   * min to a max level, then up one level above the index of the removed element. It also tests
   * that skipMe in the iterator plays nicely with forgetMeNot.
   */
  public void testIteratorInvalidatingIteratorRemove2() {

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *

But when checking benchmarks and comparisons you should keep the following in mind.

## Benchmarks and speed

  }

  /**
   * Called for each line found in the character data passed to {@link #add}.
   *
   * @param line a line of text (possibly empty), without any line separators
   * @param end the line separator; one of {@code "\r"}, {@code "\n"}, {@code "\r\n"}, or {@code ""}
   * @throws IOException if an I/O error occurs
   */
  protected abstract void handleLine(String line, String end) throws IOException;