code: def atleast2d_or_csr(X, dtype=None, order=None, copy=False):
      
      return _atleast2d_or_sparse(X, dtype, order, copy, sp.csr_matrix,
                                  "tocsr", sp.isspmatrix_csr)
docs: Like numpy.atleast_2d, but converts sparse matrices to CSR format
  
      Also, converts np.matrix to np.ndarray.