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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 variables(package):
 """ Return a dictionary of all the variables defined in the .pc pkg-config file of 'package'. """

    _raise_if_not_exists(package)
    result = _query(package, '--print-variables')
    names = (x.strip() for x in result.split('\n') if x != '')
    return dict(((x, _query(package, '--variable={0}'.format(x)).strip()) for x in names))