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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 copy_file_internal( src_fs, # type: FS src_path, # type: Text dst_fs, # type: FS dst_path, # type: Text ):
 """Low level copy, that doesn't call manage_fs or lock. If the destination exists, and is a file, it will be first truncated. This method exists to optimize copying in loops. In general you should prefer `copy_file`. Arguments: src_fs (FS):
 Source filesystem. src_path (str):
 Path to a file on the source filesystem. dst_fs (FS: Destination filesystem. dst_path (str):
 Path to a file on the destination filesystem. """

    if src_fs is dst_fs:
        # Same filesystem, so we can do a potentially optimized
        # copy
        src_fs.copy(src_path, dst_path, overwrite=True)
    elif dst_fs.hassyspath(dst_path):
        with dst_fs.openbin(dst_path, "w") as write_file:
            src_fs.download(src_path, write_file)
    else:
        with src_fs.openbin(src_path) as read_file:
            dst_fs.upload(dst_path, read_file)