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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def area_of_a_triangle_in_cartesian_space( a, b, c ):
 """ Returns the area of a triangle defined by three points in Cartesian space. Args: a (np.array):
 Cartesian coordinates of point A. b (np.array):
 Cartesian coordinates of point B. c (np.array):
 Cartesian coordinates of point C. Returns: (float):
 the area of the triangle. """

    return 0.5 * np.linalg.norm( np.cross( b-a, c-a ) )