environment/lib/python2.7/site-packages/IPython/nbformat/current.py
def writes(nb, format, **kwargs):
    """Write a notebook to a string in a given format in the current nbformat version.

    This function always writes the notebook in the current nbformat version.

    Parameters
    ----------
    nb : NotebookNode
        The notebook to write.
    format : (u'json', u'ipynb', u'py')
        The format to write the notebook in.

    Returns
    -------
    s : unicode
        The notebook string.
    """
    format = unicode(format)
    if format == u'json' or format == u'ipynb':
        return writes_json(nb, **kwargs)
    elif format == u'py':
        return writes_py(nb, **kwargs)
    else:
        raise NBFormatError('Unsupported format: %s' % format)
def writes(nb, format, **kwargs):
    """Write a notebook to a string in a given format in the current nbformat version.

    This function always writes the notebook in the current nbformat version.

    Parameters
    ----------
    nb : NotebookNode
        The notebook to write.
    format : (u'json', u'ipynb', u'py')
        The format to write the notebook in.

    Returns
    -------
    s : unicode
        The notebook string.
    """
    format = unicode(format)
    if format == u'json' or format == u'ipynb':
        return writes_json(nb, **kwargs)
    elif format == u'py':
        return writes_py(nb, **kwargs)
    else:
        raise NBFormatError('Unsupported format: %s' % format)
Write a notebook to a string in a given format in the current nbformat version.

    This function always writes the notebook in the current nbformat version.

    Parameters
    ----------
    nb : NotebookNode
        The notebook to write.
    format : (u'json', u'ipynb', u'py')
        The format to write the notebook in.

    Returns
    -------
    s : unicode
        The notebook string.