> ## Documentation Index
> Fetch the complete documentation index at: https://docs.sourcery.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Extract Duplicate Method

#### Sourcery refactoring id: `extract-duplicate-method`

#### Description:

Identifies duplicate sections of code in a function and extracts these into
their own method

**Requires Sourcery Pro**

#### Before:

```python
def extraction_example():
    self.speed_slider = Scale(
        self.parent, from_=1, to=10, orient=HORIZONTAL, label="Speed"
    )
    self.speed_slider.pack()
    self.speed_slider.set(DEFAULT_SPEED)
    self.speed_slider.configure(background="white")

    self.force_slider = Scale(
        self.parent, from_=1, to=10, orient=HORIZONTAL, label="Force"
    )
    self.force_slider.pack()
    self.force_slider.set(DEFAULT_FORCE)
    self.force_slider.configure(background="white")
```

#### After:

```python
def extraction_example():
    self.speed_slider = _extracted_from_extraction_example_2(
        self, "Speed", DEFAULT_SPEED
    )
    self.force_slider = _extracted_from_extraction_example_2(
        self, "Force", DEFAULT_FORCE
    )


def _extracted_from_extraction_example_2(self, label, arg2):
    result = Scale(self.parent, from_=1, to=10, orient=HORIZONTAL, label=label)
    result.pack()
    result.set(arg2)
    result.configure(background="white")

    return result
```

#### Explanation:

Do not Repeat Yourself (DRY) is an important tenet of writing clean,
maintainable code. Duplicated code bloats the code base, making it harder to
read and understand. It often also leads to bugs. Where changes are made in only
some of the duplicated areas unintended behaviour will often arise.

One of the main ways to remove duplication is to extract the common areas into
another method and call that. Sourcery can detect areas of duplicate code that
are in the same function and extract them. It is recommended that you then
rename the extracted function and any arguments that have not been automatically
named. In the above example a suitable method name would be `create_slider`, and
`arg2` would be `default_value`.