Python Pathlib path object not converting to string

I am trying to use Shutil to copy a pdf file using path objects from Pathlib, however when I run my code I get the error "str object is not callable" when converting my paths back to strings using str(). Any explanation for why this is occurring would be very helpful. Thanks!

from pathlib import Path
from wand.image import Image as wandImage
import shutil
import sys
import os

def pdf2Jpeg(pdf_path):
    pdf = pdf_path
    jpg = pdf[:-3] + "jpg"
    img = wandImage(filename=pdf)
    img.save(filename=jpg)

src0 = Path(r"G:\Well Schematics\Well Histories\Merged")
dst0 = Path(r"G:\Well Schematics\Well Histories\Out")
if not dst0.exists():
    dst0.mkdir()

pdfs = []
api = ''
name = ''
pnum = ''
imgs = []

for pdf in src0.iterdir():
    pdfs.append(pdf)

for pdf in pdfs:

    if not dst0.exists():
        dst0.mkdir()

    str = str(pdf.stem)
    split = str.split('_')
    api = split[0]
    name = split[1]
    pnum = split[2]

    shutil.copy(str(pdf), str(dst0))
    for file in dst0.iterdir():
        newpdf = file
    pdf2Jpeg(str(newpdf))
    newpdf.unlink()