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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 atleast2d_or_csr(X, dtype=None, order=None, copy=False):
 """Like numpy.atleast_2d, but converts sparse matrices to CSR format Also, converts np.matrix to np.ndarray. """

    return _atleast2d_or_sparse(X, dtype, order, copy, sp.csr_matrix,
                                "tocsr", sp.isspmatrix_csr)