Manipulating filenames using Python I was tasked with creating a script to be able to rename some files and then move them into different folders based on a code in the filename.

import os
import shutil

path = (r"C:\user\reports")

filelist = [ f for f in os.listdir(path) if f.endswith(".xml") ]

for f in filelist:
    x = os.path.join(path, f)
    os.remove(x)

filelist = [ f for f in os.listdir(path) if f.endswith(".pdf") ]


for f in filelist:
    os.rename(os.path.join(path, f),os.path.join(path, f[31:]))


filelist = [f for f in os.listdir(path) if f.endswith(".pdf")]

for f in filelist:    
    if "A" in f[-6:]: shutil.copy(os.path.join(path, f),r"C:\user\reports\folderA")
    if "B" in f[-6:]: shutil.copy(os.path.join(path, f),r"C:\user\reports\folderB")
    if "C" in f[-6:]: shutil.copy(os.path.join(path, f),r"C:\user\reports\folderC")
    if "D" in f[-6:]: shutil.copy(os.path.join(path, f),r"C:\user\reports\folderD")
    if "E" in f[-6:]: shutil.copy(os.path.join(path, f),r"C:\user\reports\folderE")
    if "F" in f[-6:]: shutil.copy(os.path.join(path, f),r"C:\user\reports\folderF")
    if "G" in f[-6:]: shutil.copy(os.path.join(path, f),r"C:\user\reports\folderG")
    if "H" in f[-6:]: shutil.copy(os.path.join(path, f),r"C:\user\reports\folderH")
    if "I" in f[-6:]: shutil.copy(os.path.join(path, f),r"C:\user\reports\folderI") 

filelist = [f for f in os.listdir(path) if f.endswith(".pdf")]

for f in filelist:
    x = os.path.join(path, f)
    os.remove(x)


First, it removes any XML files in the folder. Then it strips the first 31 characters (it will always be 31 characters) of the filename, leaving just a name and a code. It then checks if the final 6 characters contain a "code" and then move the file to the correct folder based off that code. After every file has been moved, it will delete every file in the parent folder. 

I know my current code could be improved, but it's been a couple of years since I've done Python so I've literally done it the easiest way (from what I could Google) possible. Any improvements or suggestions to what features of Python I should be looking at would be great.
Don't reinvent the wheel

For getting the files with a specific extension you should use glob:

xmlFiles = glob.glob('*.xml')


(Note that this will work relative to the current path.)

Avoid code duplication

You have some serious code duplication going on, replace it my appropriate code like:

#I don't really know the semantics of your paths so you should rename this accordingly
allowedPaths = 'ABCDEFGHI'
for filename in filelist:    
    for character in allowedPaths:
        if character in f[-6:]: shutil.copy(os.path.join(path, f), 
                                            os.join.path(path, r"folder" + character))


Magic numbers

Avoid these magic numbers by replacing them with "constants"

PREFIX_LENGTH = 31
POSTFIX_LENGTH = 6
#...
os.rename(os.path.join(path, f),os.path.join(path, f[PREFIX_LENGTH:]))
#...
if character in f[-POSTFIX_LENGTH:]: