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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_if_newer( src_fs, # type: Union[FS, Text] src_path, # type: Text dst_fs, # type: Union[FS, Text] dst_path, # type: Text ):
 """Copy a file from one filesystem to another, checking times. If the destination exists, and is a file, it will be first truncated. If both source and destination files exist, the copy is executed only if the source file is newer than the destination file. In case modification times of source or destination files are not available, copy is always executed. Arguments: src_fs (FS or str):
 Source filesystem (instance or URL). src_path (str):
 Path to a file on the source filesystem. dst_fs (FS or str):
 Destination filesystem (instance or URL). dst_path (str):
 Path to a file on the destination filesystem. Returns: bool: `True` if the file copy was executed, `False` otherwise. """

    with manage_fs(src_fs, writeable=False) as _src_fs:
        with manage_fs(dst_fs, create=True) as _dst_fs:
            if _src_fs is _dst_fs:
                # Same filesystem, so we can do a potentially optimized
                # copy
                if _source_is_newer(_src_fs, src_path, _dst_fs, dst_path):
                    _src_fs.copy(src_path, dst_path, overwrite=True)
                    return True
                else:
                    return False
            else:
                # Standard copy
                with _src_fs.lock(), _dst_fs.lock():
                    if _source_is_newer(_src_fs, src_path, _dst_fs, dst_path):
                        copy_file_internal(_src_fs, src_path, _dst_fs, dst_path)
                        return True
                    else:
                        return False