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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 find_vasp_calculations():
 """ Returns a list of all subdirectories that contain either a vasprun.xml file or a compressed vasprun.xml.gz file. Args: None Returns: (List):
 list of all VASP calculation subdirectories. """

    dir_list = [ './' + re.sub( r'vasprun\.xml', '', path ) for path in glob.iglob( '**/vasprun.xml', recursive=True ) ]
    gz_dir_list = [ './' + re.sub( r'vasprun\.xml\.gz', '', path ) for path in glob.iglob( '**/vasprun.xml.gz', recursive=True ) ]
    return dir_list + gz_dir_list