To plot a histogram with a density plot in Python, you can use the seaborn library.
First, install the seaborn library:
```
pip install seaborn
```
Next, import the libraries:
```
import seaborn as sns
import matplotlib.pyplot as plt
```
Now, create the data, and assign it to a variable:
```
data = [1,2,3,3,3,3,3,4,5,6,7,7,7,8,9]
```
Then, call the seaborn libraryand specify the histogram with a density plot, with the data and number of bins:
```
sns.distplot(data, bins=10, kde=True)
```
Finally, call the plot to display the figure:
```
plt.show()
```
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