if (!components.get(i).apply(t)) {
          return false;
        }
      }
      return true;
    }

    @Override
    public int hashCode() {
      // add a random number to avoid collisions with OrPredicate
      return components.hashCode() + 0x12472c2c;
    }

    @Override
    public boolean equals(@Nullable Object obj) {
      if (obj instanceof AndPredicate) {

```

To learn more about Python Packages and Modules, read [the official Python documentation about Modules](https://docs.python.org/3/tutorial/modules.html).

///

### Avoid name collisions { #avoid-name-collisions }

We are importing the submodule `items` directly, instead of importing just its variable `router`.

This is because we also have another variable named `router` in the submodule `users`.

        if (!components.get(i).apply(t)) {
          return false;
        }
      }
      return true;
    }

    @Override
    public int hashCode() {
      // add a random number to avoid collisions with OrPredicate
      return components.hashCode() + 0x12472c2c;
    }

    @Override
    public boolean equals(@Nullable Object obj) {
      if (obj instanceof AndPredicate) {

 * including those in many JDK classes.
 *
 * <p>{@code Object.hashCode} implementations tend to be very fast, but have weak collision
 * prevention and <i>no</i> expectation of bit dispersion. This leaves them perfectly suitable for
 * use in hash tables, because extra collisions cause only a slight performance hit, while poor bit
 * dispersion is easily corrected using a secondary hash function (which all reasonable hash table

   *
   * <p>This is designed for generating persistent fingerprints of strings. It isn't
   * cryptographically secure, but it produces a high-quality hash with fewer collisions than some
   * alternatives we've used in the past.
   *
   * <p>FarmHash fingerprints are encoded by {@link HashCode#asBytes} in little-endian order. This

#include "tensorflow/core/platform/errors.h"

namespace tensorflow {
namespace gradients {
namespace {

// TODO(b/172558015): Using the pointer address as the identifier for the tensor
// may lead to collisions. Introduce another way to get a unique id for this
// tensor.
int64_t ToId(const AbstractTensorHandle* t) {
  return static_cast<int64_t>(reinterpret_cast<uintptr_t>(t));
}

   *       </ul>
   *   <li>another java.util.Set delegate implementation. In most modern JDKs, normal java.util hash
   *       collections intelligently fall back to a binary search tree if hash table collisions are
   *       detected. Rather than going to all the trouble of reimplementing this ourselves, we
   *       simply switch over to use the JDK implementation wholesale if probable hash flooding is

   * bulkGet(keys)} operation. See <a href="http://www.mathpages.com/home/kmath199.htm">Balls in
   * Bins model</a> for mathematical formulas that can be used to estimate the probability of
   * collisions.
   *
   * @param keys arbitrary non-null keys
   * @return the stripes corresponding to the objects (one per each object, derived by delegating to

   *       </ul>
   *   <li>another java.util.Map delegate implementation. In most modern JDKs, normal java.util hash
   *       collections intelligently fall back to a binary search tree if hash table collisions are
   *       detected. Rather than going to all the trouble of reimplementing this ourselves, we
   *       simply switch over to use the JDK implementation wholesale if probable hash flooding is

第二个版本是「绝对导入」：

```Python
from app.routers import items, users
```

要了解有关 Python 包和模块的更多信息，请查阅[关于 Modules 的 Python 官方文档](https://docs.python.org/3/tutorial/modules.html)。

///

### 避免名称冲突 { #avoid-name-collisions }

我们将直接导入 `items` 子模块，而不是仅导入其 `router` 变量。

这是因为我们在 `users` 子模块中也有另一个名为 `router` 的变量。

如果我们一个接一个地导入，例如：

```Python
from .routers.items import router
from .routers.users import router
```