Get the root directory for all zipline-managed files.

    For testing purposes, this accepts a dictionary to interpret as the os
    environment.

    Parameters
    ----------
    environ : dict, optional
        A dict to interpret as the os environment.

    Returns
    -------
    root : string
        Path to the zipline root dir.

def zipline_root(environ=None):
    """
    Get the root directory for all zipline-managed files.

    For testing purposes, this accepts a dictionary to interpret as the os
    environment.

    Parameters
    ----------
    environ : dict, optional
        A dict to interpret as the os environment.

    Returns
    -------
    root : string
        Path to the zipline root dir.
    """
    if environ is None:
        environ = os.environ

    root = environ.get('ZIPLINE_ROOT', None)
    if root is None:
        root = expanduser('~/.zipline')

    return root