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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 get_metadata_for_nifti(in_file, bids_dir=None, validate=True):
 """Fetch metadata for a given nifti file 'SIEMENS' """

    return _init_layout(in_file, bids_dir, validate).get_metadata(
        str(in_file))