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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(self):
 r"""The area of the current curved polygon. This assumes, but does not check, that the current curved polygon is valid (i.e. it is bounded by the edges). This computes the area via Green's theorem. Using the vector field :math:`\mathbf{F} = \left[-y, x\right]^T`, since :math:`\partial_x(x) - \partial_y(-y) = 2` Green's theorem says .. math:: \int_{\mathcal{P}} 2 \, d\textbf{x} = \int_{\partial \mathcal{P}} -y \, dx + x \, dy (where :math:`\mathcal{P}` is the current curved polygon). Note that for a given edge :math:`C(r)` with control points :math:`x_j, y_j`, the integral can be simplified: .. math:: \int_C -y \, dx + x \, dy = \int_0^1 (x y' - y x') \, dr = \sum_{i < j} (x_i y_j - y_i x_j) \int_0^1 b_{i, d} b'_{j, d} \, dr where :math:`b_{i, d}, b_{j, d}` are Bernstein basis polynomials. Returns: float: The area of the current curved polygon. """

        edges = tuple(edge._nodes for edge in self._edges)
        return _surface_helpers.compute_area(edges)