alternative coo implementation

coo.py

class coo_matrix(_data_matrix, _minmax_mixin):
    ...
    
    format = 'coo'

    def __init__(self, arg1, shape=None, dtype=None, copy=False):
        ...
            else:
                #dense argument
                
                array_data = np.asarray(arg1)
                
                if array_data.ndim = 1:
                  M = coo_1d(M)
                if array_data.ndim = 2:
                  M = coo_2d(M)
                if array_data.ndim > 2:
                  raise TypeError('expected dimension <= 2 array or matrix')
                else:
                  self._shape = check_shape(array_data.shape)

                self.row, self.col = M.nonzero()
                self.data = M[self.row, self.col]
                self.has_canonical_format = True

        if dtype is not None:
            self.data = self.data.astype(dtype, copy=False)

        self._check()