1. Import matplotlib:

>>> import matplotlib.pyplot as plt

2. Prepare the data. This represents two products' sales:

>>> DATA = (
...     ('Q1 2017', 100, 5),
...     ('Q2 2017', 105, 15),
...     ('Q3 2017', 125, 40),
...     ('Q4 2017', 115, 80),
... )

3. Process the data to prepare the expected format:

>>> POS = list(range(len(DATA)))
>>> VALUESA = [valueA for label, valueA, valueB in DATA]
>>> VALUESB = [valueB for label, valueA, valueB in DATA]
>>> LABELS = [label for label, value1, value2 in DATA]

4. Create the line plot. Two lines are required:

>>> plt.plot(POS, VALUESA, 'o-')
>>> plt.plot(POS, VALUESB, 'o-')
>>> plt.ylabel('Sales')
>>> plt.xticks(POS, LABELS)

5. Display the graph:

>>> plt.show()

6. The result will be displayed in a new window: