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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def remove_var(var):
    '''
    Remove a variable from the make.conf

    Return a dict containing the new value for the variable::

        {'<variable>': {'old': '<old-value>',
                        'new': '<new-value>'}}

    CLI Example:

    .. code-block:: bash

        salt '*' makeconf.remove_var 'LINGUAS'
    '''
    makeconf = _get_makeconf()

    old_value = get_var(var)

    # If var is in file
    if old_value is not None:
        __salt__['file.sed'](makeconf, '^{0}=.*'.format(var), '')

    new_value = get_var(var)
    return {var: {'old': old_value, 'new': new_value}}