Thanks guys! Here's the program I ended up writing in case anyone wants to do the same thing!

def gene_alias(gene_file):
from Bio import Entrez
import csv

Entrez.email = "your email"
genes = [gene.rstrip('\n') for gene in open(gene_file)]

ids = []
aliases = []

for gene in genes:
    #retrieve gene ID
    handle = Entrez.esearch(db="gene", term="Mus musculus[Orgn] AND " + gene + "[Gene]")
    record = Entrez.read(handle)

    if len(record["IdList"]) > 0:
        ids.append(record["IdList"][0])

        #retrieve aliases
        record_with_aliases = Entrez.efetch(db="gene",id=record["IdList"][0],retmode="json")
        entry = record_with_aliases.read()
        entry_lines = entry.splitlines()
        for i in range(len(entry_lines)):
            while 'This record was replaced with GeneID:' in entry_lines[i]:
               new_id = entry_lines[i][38:]
               record_with_aliases = Entrez.efetch(db="gene",id=new_id ,retmode="json")
               entry = record_with_aliases.read()
               entry_lines = entry.splitlines()


        firstline = entry.splitlines()[1]
        if gene.lower() == firstline[3:].lower():
            thirdline = entry.splitlines()[3]
            fourthline = entry.splitlines()[4]
            if thirdline[0:13] == 'Other Aliases':
                aliases.append(thirdline[15:])
            elif fourthline == 'This record was discontinued.':
                aliases.append(fourthline)
            else:
                aliases.append('no aliases')
        else:
            aliases.append(firstline[3:])

    else:
        ids.append(gene + ' is not in Gene')
        aliases.append(gene + ' is not in Gene')

rows = zip(genes, ids, aliases)
with open('gene_aliases.csv', 'wb') as thefile:
    writer = csv.writer(thefile)
    writer.writerow(['Gene', 'ID', 'Aliases'])
    for row in rows:
        writer.writerow(row)