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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 _get_unique_variable_name(vname, variables):
    '''Get a unique variable name.

    Args:
        vname(str): A candidate name.
        variable(OrderedDict of str and Variable)

    Returns: str
        A unique variable name
    '''
    count = 2
    vname_base = vname
    while vname in variables:
        vname = '{}_{}'.format(vname_base, count)
        count += 1
    return vname