<img src="/images/kartinka1.jpg" border=0 width=10 height=10><br>
<img src="/images/kartinka2.jpg" border=0 width=10 height=10>

import urllib.request
urllib.request.urlretrieve ("http://site.com/images/capture.jpg", "logo.jpg")

    rex = re.compile(r'(img src=(\")?)(.*?)(\")')
    img = [d[2] for d in rex.findall(html)

import re
text = '''<img src="/images/kartinka1.jpg" border=0 width=10 height=10 ><br>
<img src="/images/kartinka2.jpg" border= 0 width=10 height=10>'''
pattern = r'<img src="([^"]+)"'
for img in re.findall(pattern, text):
    print(img)

/images/kartinka1.jpg
/images/kartinka2.jpg

/images/kartinka1.jpg

import re
text = '''<img src="/images/kartinka1.jpg" border=0 width=10 height=10 ><br>
<img src="/images/kartinka2.jpg" border= 0 width=10 height=10>'''
pattern = r'<img src="([^"]+)"'
scr = re.search(pattern, text)
if scr:
    print(scr.group(1))