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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 displaceAbs(x, y, sourcePos_x, sourcePos_y):
 """ calculates a grid of distances to the observer in angel :param mapped_cartcoord: mapped cartesian coordinates :type mapped_cartcoord: numpy array (n,2) :param sourcePos: source position :type sourcePos: numpy vector [x0,y0] :returns: array of displacement :raises: AttributeError, KeyError """

    x_mapped = x - sourcePos_x
    y_mapped = y - sourcePos_y
    absmapped = np.sqrt(x_mapped**2+y_mapped**2)
    return absmapped