parameters: (tensor)
return_statement: return isinstance(tensor, sparse_tensor.SparseTensor)
docstring: Returns whether a tensor is a sparse tensor.
  
    Arguments:
        tensor: A tensor instance.
  
    Returns:
        A boolean.
  
    Example:
    ```python
    >>> from keras import backend as K
    >>> a = K.placeholder((2, 2), sparse=False)
    >>> print(K.is_sparse(a))
    False
    >>> b = K.placeholder((2, 2), sparse=True)
    >>> print(K.is_sparse(b))
    True
    ```
docstring_summary: Returns whether a tensor is a sparse tensor.
docstring_tokens: Returns whether a tensor is a sparse tensor .
function: def is_sparse(tensor):
    """Returns whether a tensor is a sparse tensor.
  
    Arguments:
        tensor: A tensor instance.
  
    Returns:
        A boolean.
  
    Example:
    ```python
    >>> from keras import backend as K
    >>> a = K.placeholder((2, 2), sparse=False)
    >>> print(K.is_sparse(a))
    False
    >>> b = K.placeholder((2, 2), sparse=True)
    >>> print(K.is_sparse(b))
    True
    ```
    """
    return isinstance(tensor, sparse_tensor.SparseTensor)
function_tokens: def is_sparse ( tensor ) : return isinstance ( tensor , sparse_tensor . SparseTensor )