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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 variable_name(value, allow_empty = False, **kwargs):
 """Validate that the value is a valid Python variable name. .. caution:: This function does **NOT** check whether the variable exists. It only checks that the ``value`` would work as a Python variable (or class, or function, etc.) name. :param value: The value to validate. :param allow_empty: If ``True``, returns :obj:`None <python:None>` if ``value`` is empty. If ``False``, raises a :class:`EmptyValueError <validator_collection.errors.EmptyValueError>` if ``value`` is empty. Defaults to ``False``. :type allow_empty: :class:`bool <python:bool>` :returns: ``value`` / :obj:`None <python:None>` :rtype: :class:`str <python:str>` or :obj:`None <python:None>` :raises EmptyValueError: if ``allow_empty`` is ``False`` and ``value`` is empty """

    if not value and not allow_empty:
        raise errors.EmptyValueError('value (%s) was empty' % value)
    elif not value:
        return None

    try:
        parse('%s = None' % value)
    except (SyntaxError, ValueError, TypeError):
        raise errors.InvalidVariableNameError(
            'value (%s) is not a valid variable name' % value
        )

    return value