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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 is_valid_input_meshgrid(x, ndim):
 """Test if ``x`` is a `meshgrid` sequence for points in R^d."""

    # This case is triggered in FunctionSpaceElement.__call__ if the
    # domain does not have an 'ndim' attribute. We return False and
    # continue.
    if ndim is None:
        return False

    if not isinstance(x, tuple):
        return False

    if ndim > 1:
        try:
            np.broadcast(*x)
        except (ValueError, TypeError):  # cannot be broadcast
            return False

    return (len(x) == ndim and
            all(isinstance(xi, np.ndarray) for xi in x) and
            all(xi.ndim == ndim for xi in x))