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05-data-classes/typing_namedtuple/coordinates2.py

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+"""
+``Coordinate``: a simple ``NamedTuple`` subclass
+
+This version has a field with a default value::
+
+    >>> moscow = Coordinate(55.756, 37.617)
+    >>> moscow
+    Coordinate(lat=55.756, lon=37.617, reference='WGS84')
+
+"""
+
+# tag::COORDINATE[]
+from typing import NamedTuple
+
+class Coordinate(NamedTuple):
+
+    lat: float                # <1>
+    lon: float
+    reference: str = 'WGS84'  # <2>
+# end::COORDINATE[]