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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 vasp_version_from_outcar( filename='OUTCAR' ):
 """ Returns the first line from a VASP OUTCAR file, to get the VASP source version string. Args: filename (Str, optional):
 OUTCAR filename. Defaults to 'OUTCAR'. Returns: (Str):
 The first line read from the OUTCAR file. """

    with open( filename ) as f:
        line = f.readline().strip()
    return line