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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 _block_shape(values, ndim=1, shape=None):
 """ guarantee the shape of the values to be at least 1 d """

    if values.ndim < ndim:
        if shape is None:
            shape = values.shape
        if not is_extension_array_dtype(values):
            # TODO: https://github.com/pandas-dev/pandas/issues/23023
            # block.shape is incorrect for "2D" ExtensionArrays
            # We can't, and don't need to, reshape.
            values = values.reshape(tuple((1, ) + shape))
    return values