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Given the following text description, write Python code to implement the functionality described below step by step
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Description:
 Plotting two variables as lines on the same graph
So you've got 2 variables and you want to plot them on the same chart? How do you do it in ggplot? Well good news is it's super easy to do with ggplot!
We're going to use a subset of the meat dataset for this example. We're going to use pandas to switch our data from "wide" to "long" format.
Step1:  Now we'll setup our aesthetics so date is the x-axis value, variable is the color of each line and value is the y-axis value.
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Python Code:
meat_subset = meat[['date', 'beef', 'pork']]
df = pd.melt(meat_subset, id_vars=['date'])
df.head()
Explanation: Plotting two variables as lines on the same graph
So you've got 2 variables and you want to plot them on the same chart? How do you do it in ggplot? Well good news is it's super easy to do with ggplot!
We're going to use a subset of the meat dataset for this example. We're going to use pandas to switch our data from "wide" to "long" format.
End of explanation
ggplot(df, aes(x='date', y='value', color='variable')) + geom_line()
Explanation: Now we'll setup our aesthetics so date is the x-axis value, variable is the color of each line and value is the y-axis value.
End of explanation
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