an be opened for reading or writing.  The special value ``-``
    indicates stdin or stdout depending on the mode.

    By default, the file is opened for reading text data, but it can also be
    opened in binary mode or for writing.  The encoding parameter can be used
    to force a specific encoding.

    The `lazy` flag controls if the file should be opened immediately or upon
    first IO. The default is to be non-lazy for standard input and output
    streams as well as files opened for reading, `lazy` otherwise. When opening a
    file lazily for reading, it is still opened temporarily for validation, but
    will not be held open until first IO. lazy is mainly useful when opening
    for writing to avoid creating the file until it is needed.

    Starting with Click 2.0, files can also be opened atomically in which
    case all writes go into a separate file in the same folder and upon
    completion the file will be moved over to the original location.  This
    is useful if a file regularly read by other users is modified.

    See :ref:`file-args` for more information.
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