### Dataframes
### Accessing Data in a Dataframe
1. Square Brackets Method (`df['column_name']`):
2. Dot Notation Method (`df.column_name`):
### Data Cleansing in Dataframes
#### Handling Nulls
- `df.dropna()`
- `df.fillna()`
### Data Manipulation
#### Sorted Data in a Dataframe
- `df.sort_values()
```python
df_sorted = df.sort_values(by='A')
print("1. sort_values():")
print(df_sorted)
```