How do I take one column of a Pandas dataframe and make it become part of the index?

You can take one column of a Pandas DataFrame and set it as the index using the `set_index` method. Here's an example:

```python

import pandas as pd

# Create a sample DataFrame

data = {'Name': ['Alice', 'Bob', 'Charlie'],

        'Age': [25, 30, 22],

        'City': ['New York', 'San Francisco', 'Los Angeles']}

df = pd.DataFrame(data)

# Display the original DataFrame

print("Original DataFrame:")

print(df)

# Set the 'Name' column as the index

df.set_index('Name', inplace=True)

# Display the DataFrame with the updated index

print("\nDataFrame with 'Name' as the index:")

print(df)

```

In this example, the `set_index('Name', inplace=True)` line sets the 'Name' column as the index of the DataFrame. The `inplace=True` parameter modifies the DataFrame in place, meaning the change is applied directly to the existing DataFrame rather than creating a new one.

The resulting DataFrame will have the 'Name' column as its index. You can replace 'Name' with the name of the column you want to set as the index in your specific DataFrame.

Note: If you don't use `inplace=True`, the `set_index` method will return a new DataFrame with the specified index, and you need to assign it back to your original DataFrame or a new variable.