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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 _pname_and_metadata(in_file):
 """Retrieve metadata and project name from the input metadata CSV file. Uses the input file name for the project name and for back compatibility, accepts the project name as an input, providing no metadata. """

    if os.path.isfile(in_file):
        with open(in_file) as in_handle:
            md, global_vars = _parse_metadata(in_handle)
        base = os.path.splitext(os.path.basename(in_file))[0]
        md_file = in_file
    elif objectstore.is_remote(in_file):
        with objectstore.open_file(in_file) as in_handle:
            md, global_vars = _parse_metadata(in_handle)
        base = os.path.splitext(os.path.basename(in_file))[0]
        md_file = None
    else:
        if in_file.endswith(".csv"):
            raise ValueError("Did not find input metadata file: %s" % in_file)
        base, md, global_vars = _safe_name(os.path.splitext(os.path.basename(in_file))[0]), {}, {}
        md_file = None
    return _safe_name(base), md, global_vars, md_file