<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def _get_hydrated_path(field):
 """Return HydratedPath object for file-type field."""

    # Get only file path if whole file object is given.
    if isinstance(field, str) and hasattr(field, 'file_name'):
        # field is already actually a HydratedPath object
        return field

    if isinstance(field, dict) and 'file' in field:
        hydrated_path = field['file']

    if not hasattr(hydrated_path, 'file_name'):
        raise TypeError("Filter argument must be a valid file-type field.")

    return hydrated_path