Inserting the same value multiple times when formatting a string
You can use the dictionary type of formatting:
s='arbit'
string='%(key)s hello world %(key)s hello world %(key)s' % {'key': s,}
You can use advanced string formatting, available in Python 2.6 and Python 3.x:
incoming = 'arbit'
result = '{0} hello world {0} hello world {0}'.format(incoming)
incoming = 'arbit'
result = '%(s)s hello world %(s)s hello world %(s)s' % {'s': incoming}
You may like to have a read of this to get an understanding: String Formatting Operations.